RRB ALP Online Test Series 1, RRB ALP Mock Test, RRB Quiz
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RRB ALP Online Test in English Series 1, RRB ALP Free Online Test Series 1. RRB Exam Online Test 2021, RRB ALP Free Mock Test Exam 2021. RRB ALP Exam Free Online Quiz 2021, RRB ALP Full Online Mock Test Series 1st in English. RRB Online Test for All Subjects, RRB ALP Free Mock Test Series in English. RRB ALP Free Mock Test Series 1. RRB ALP English Language Online Test in English Series 1st. RRB ALP Quantitative Aptitude Quiz 2021, RRB ALP Reasoning Ability Free Online Test. Take RRB ALP Online Quiz. The RRB ALP Full online mock test paper is free for all students. RRB ALP Question and Answers in English and Hindi Series 1. Here we are providing RRB ALP Full Mock Test Paper in English. RRB ALP Mock Test Series 1st 2021. Now Test your self for RRB ALP Exam by using below quiz…
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Question 1 of 50
1. Question
In what time will a railway train 60 m long moving at the rate of 36 kmph pass a telegraph post on its way?
Correct
T = 60/36 * 18/5 = 6 sec
Incorrect
T = 60/36 * 18/5 = 6 sec

Question 2 of 50
2. Question
Rs. 800 becomes Rs. 956 in 3 years at a rate of S.I. If the rate of interest is increased by 4%, what amount will Rs. 800 become in 3 years?
Correct
S.I. = (956 – 800) = Rs. 156.
Rate = (100 * 156) / (800 * 3) = 6 1/2 %
Now rate = (6 1/2 + 4) = 10 1/2 %
New S.I. = (800 * 21/2 * 3/100) = Rs. 252
New amount = (800 + 252) = Rs. 1052.Incorrect
S.I. = (956 – 800) = Rs. 156.
Rate = (100 * 156) / (800 * 3) = 6 1/2 %
Now rate = (6 1/2 + 4) = 10 1/2 %
New S.I. = (800 * 21/2 * 3/100) = Rs. 252
New amount = (800 + 252) = Rs. 1052. 
Question 3 of 50
3. Question
In the first 10 overs of a cricket game, the run rate was only 3.2. What should be the rate in the remaining 40 overs to reach the target of 282 runs?
Correct
Required run rate
= [282 – (3.2 * 10)]/40 = 250/40 = 6.25Incorrect
Required run rate
= [282 – (3.2 * 10)]/40 = 250/40 = 6.25 
Question 4 of 50
4. Question
The area of a parallelogram is 128sq m and its altitude is twice the corresponding base. Then the length of the base is?
Correct
2x * x = 128 => x= 8
Incorrect
2x * x = 128 => x= 8

Question 5 of 50
5. Question
A man can row his boat with the stream at 6 km/h and against the stream in 4 km/h. The man’s rate is?
Correct
DS = 6
US = 4
S = ?
S = (6 – 4)/2 = 1 kmphIncorrect
DS = 6
US = 4
S = ?
S = (6 – 4)/2 = 1 kmph 
Question 6 of 50
6. Question
Which of the following is the greatest?
Correct
In choice (b), the base 333 lies between 243 = (3^{5}) and 729 = (3^{6}) 3333 lies between 3^{7} and 3^{8}Hence 333^{3} lies between (3^{5})^{3} and (3^{6})^{3}, i.e., between 3^{15} and 3^{18}In choice (c), the base 33 lies between 27 = (3^{3}) and 81 = (3^{4}).Hence 33^{33} lies between (3^{3})^{33} and (3^{4})^{33} i.e., between 3^{99} and 3^{132}. Hence is greatest.Incorrect
In choice (b), the base 333 lies between 243 = (3^{5}) and 729 = (3^{6}) 3333 lies between 3^{7} and 3^{8}Hence 333^{3} lies between (3^{5})^{3} and (3^{6})^{3}, i.e., between 3^{15} and 3^{18}In choice (c), the base 33 lies between 27 = (3^{3}) and 81 = (3^{4}).Hence 33^{33} lies between (3^{3})^{33} and (3^{4})^{33} i.e., between 3^{99} and 3^{132}. Hence is greatest. 
Question 7 of 50
7. Question
A man can row a boat at 20 kmph in still water. If the speed of the stream is 6 kmph, what is the time taken to row a distance of 60 km downstream?
Correct
Speed downstream = 20 + 6 = 26 kmph.
Time required to cover 60 km downstream = d/s = 60/26 = 30/13 hours.Incorrect
Speed downstream = 20 + 6 = 26 kmph.
Time required to cover 60 km downstream = d/s = 60/26 = 30/13 hours. 
Question 8 of 50
8. Question
A can finish a piece of work in 5 days. B can do it in 10 days. They work together for two days and then A goes away. In how many days will B finish the work?
Correct
2/5 + (2 + x)/10 = 1 => x = 4 days
Incorrect
2/5 + (2 + x)/10 = 1 => x = 4 days

Question 9 of 50
9. Question
A is twice as good a workman as B and they took 7 days together to do the work B alone can do it in.
Correct
WC = 2:1
2x + x = 1/7
x = 1/21 => 21 daysIncorrect
WC = 2:1
2x + x = 1/7
x = 1/21 => 21 days 
Question 10 of 50
10. Question
How many cubes of edge 2 dm can be cut out of a meter cube?
Correct
1 * 1* 1 = 2/10 * 2/10 * 2/10 * x
x = 125Incorrect
1 * 1* 1 = 2/10 * 2/10 * 2/10 * x
x = 125 
Question 11 of 50
11. Question
A can do half the work in one day where as B can do it full. B can also do half the work of C in one day. Ratio in their efficiency will be?
Correct
WC of A: B = 1:2
B: C = 1:2
———————
A: B: C = 1:2:4Incorrect
WC of A: B = 1:2
B: C = 1:2
———————
A: B: C = 1:2:4 
Question 12 of 50
12. Question
The total marks obtained by a student in Physics, Chemistry and Mathematics is 150 more than the marks obtained by him in Physics. What is the average mark obtained by him in Chemistry and Mathematics?
Correct
Let the marks obtained by the student in Physics, Chemistry and Mathematics be P, C and M respectively.
P + C + M = 150 + P
C + M = 150
Average mark obtained by the student in Chemistry and Mathematics = (C + M)/2 = 150/2 = 75.Incorrect
Let the marks obtained by the student in Physics, Chemistry and Mathematics be P, C and M respectively.
P + C + M = 150 + P
C + M = 150
Average mark obtained by the student in Chemistry and Mathematics = (C + M)/2 = 150/2 = 75. 
Question 13 of 50
13. Question
A train 110 meters long is running with a speed of 60 kmph. In what time will it pass a man who is running at 6 kmph in the direction opposite to that in which the train is going?
Correct
Speed of train relative to man = (60 + 6) km/hr = 66 km/hr
[66 * 5/18] m/sec = [55/3] m/sec.
Time taken to pass the man = [110 * 3/55] sec = 6 secIncorrect
Speed of train relative to man = (60 + 6) km/hr = 66 km/hr
[66 * 5/18] m/sec = [55/3] m/sec.
Time taken to pass the man = [110 * 3/55] sec = 6 sec 
Question 14 of 50
14. Question
A train 110 m long is running with a speed of 60 km/hr. In what time will it pass a man who is running at 6 km/hr in the direction opposite to that in which the train is going?
Correct
Speed of train relative to man = 60 + 6 = 66 km/hr.
= 66 * 5/18 = 55/3 m/sec.
Time taken to pass the men = 110 * 3/55 = 6 sec.Incorrect
Speed of train relative to man = 60 + 6 = 66 km/hr.
= 66 * 5/18 = 55/3 m/sec.
Time taken to pass the men = 110 * 3/55 = 6 sec. 
Question 15 of 50
15. Question
Two pipes A and B can fill a tank in 20 and 30 minutes respectively. If both the pipes are used together, then how long will it take to fill the tank?
Correct
Part filled by A in 1 min. = 1/20
Part filled by B in 1 min. = 1/30
part filled by (A + B) in 1 min. = 1/20 + 1/30 = 1/12.
Both the pipes can fill the tank in 12 minutes.Incorrect
Part filled by A in 1 min. = 1/20
Part filled by B in 1 min. = 1/30
part filled by (A + B) in 1 min. = 1/20 + 1/30 = 1/12.
Both the pipes can fill the tank in 12 minutes. 
Question 16 of 50
16. Question
If 10% of x = 20% of y, then x:y is equal to:
Correct
10% of x = 20% of y
10x/100 = 20y/100 => x/10 = y/5
x/y = 10/5 = 2/1
x:y = 2:1.Incorrect
10% of x = 20% of y
10x/100 = 20y/100 => x/10 = y/5
x/y = 10/5 = 2/1
x:y = 2:1. 
Question 17 of 50
17. Question
The L.C.M of two numbers is 48. The numbers are in the ratio 2:3. The sum of numbers is:
Correct
Let the numbers be 2x and 3x.
Then, their L.C.M = 6x. So, 6x = 48 or x = 8.
The numbers are 16 and 24.
Hence, required sum = (16 + 24) = 40.Incorrect
Let the numbers be 2x and 3x.
Then, their L.C.M = 6x. So, 6x = 48 or x = 8.
The numbers are 16 and 24.
Hence, required sum = (16 + 24) = 40. 
Question 18 of 50
18. Question
The sum and the product of two numbers are 25 and 144 respectively, the difference of the number is?
Correct
x + y = 25
xy = 144
(x y)2 = (x + y)2 – 4xy
(x y)2 = 625 – 576 => (x – y) = 7Incorrect
x + y = 25
xy = 144
(x y)2 = (x + y)2 – 4xy
(x y)2 = 625 – 576 => (x – y) = 7 
Question 19 of 50
19. Question
In a game of billiards, A can give B 20 points in 60 and he can give C 30 points in 60. How many points can B give C in a game of 100?
Correct
A scores 60 while B score 40 and C scores 30.
The number of points that C scores when B scores 100 = (100 * 30)/40 = 25 * 3 = 75.
In a game of 100 points, B gives (100 – 75) = 25 points to C.Incorrect
A scores 60 while B score 40 and C scores 30.
The number of points that C scores when B scores 100 = (100 * 30)/40 = 25 * 3 = 75.
In a game of 100 points, B gives (100 – 75) = 25 points to C. 
Question 20 of 50
20. Question
The smallest fraction, which each of 6/7, 5/14, 10/21 will divide exactly is:
Correct
Required fraction = L.C.M of 6/7, 5/14, 10/21
= (L.C.M of 6, 5, 10) / (H.C.F of 7, 14, 21) = 30/7Incorrect
Required fraction = L.C.M of 6/7, 5/14, 10/21
= (L.C.M of 6, 5, 10) / (H.C.F of 7, 14, 21) = 30/7 
Question 21 of 50
21. Question
Find the greatest number that exactly divides 35, 91 and 840?
Correct
The greatest number that exactly divides 35, 91 and 840 is the HCF of the three numbers. So, calculating HCF we get the answer 7.
Incorrect
The greatest number that exactly divides 35, 91 and 840 is the HCF of the three numbers. So, calculating HCF we get the answer 7.

Question 22 of 50
22. Question
In finding the HCF of two numbers, the last divisor was 41 and the successive quotients, starting from the first, where 2, 4 and 2. The numbers are?
Correct
Incorrect

Question 23 of 50
23. Question
Two varieties of wheat – A and B costing Rs. 9 per kg and Rs. 15 per kg were mixed in the ratio 3 : 7. If 5 kg of the mixture is sold at 25% profit, find the profit made?
Correct
Let the quantities of A and B mixed be 3x kg and 7x kg.
Cost of 3x kg of A = 9(3x) = Rs. 27x
Cost of 7x kg of B = 15(7x) = Rs. 105x
Cost of 10x kg of the mixture = 27x + 105x = Rs. 132x
Cost of 5 kg of the mixture = 132x/10x (5) = Rs. 66
Profit made in selling 5 kg of the mixture = 25/100 (cost of 5 kg of the mixture) = 25/100 * 66 = Rs. 16.50Incorrect
Let the quantities of A and B mixed be 3x kg and 7x kg.
Cost of 3x kg of A = 9(3x) = Rs. 27x
Cost of 7x kg of B = 15(7x) = Rs. 105x
Cost of 10x kg of the mixture = 27x + 105x = Rs. 132x
Cost of 5 kg of the mixture = 132x/10x (5) = Rs. 66
Profit made in selling 5 kg of the mixture = 25/100 (cost of 5 kg of the mixture) = 25/100 * 66 = Rs. 16.50 
Question 24 of 50
24. Question
The triplicate ratio of 1:2 is?
Correct
1^{3}: 2^{3} = 1:8
Incorrect
1^{3}: 2^{3} = 1:8

Question 25 of 50
25. Question
If the L.C.M of two numbers is 750 and their product is 18750, find the H.C.F of the numbers.
Correct
H.C.F = (Product of the numbers) / (Their L.C.M) = 18750/750 = 25.
Incorrect
H.C.F = (Product of the numbers) / (Their L.C.M) = 18750/750 = 25.

Question 26 of 50
26. Question
Two persons A and B take a field on rent. A puts on it 21 horses for 3 months and 15 cows for 2 months; B puts 15 cows for 6months and 40 sheep for 7 1/2 months. If one day, 3 horses eat as much as 5 cows and 6 cows as much as 10 sheep, what part of the rent should A pay?
Correct
3h = 5c
6c = 10s
A = 21h*3 + 15c*2
= 63h + 30c
= 105c + 30c = 135c
B = 15c*6 + 40s*7 1/2
= 90c + 300s
= 90c + 180c = 270c
A:B = 135:270
27:52
A = 27/79 = 1/3Incorrect
3h = 5c
6c = 10s
A = 21h*3 + 15c*2
= 63h + 30c
= 105c + 30c = 135c
B = 15c*6 + 40s*7 1/2
= 90c + 300s
= 90c + 180c = 270c
A:B = 135:270
27:52
A = 27/79 = 1/3 
Question 27 of 50
27. Question
The sum of four consecutive even numbers is 36. Find the sum of the squares of these numbers?
Correct
Let the four numbers be x, x + 2, x + 4 and x + 6.
=> x + x + 2 + x + 4 + x + 6 = 36=> 4x + 12 = 36 => x = 6The numbers are 6, 8, 10 and 12.Sum of their squares = 6^{2} + 8^{2} + 10^{2} + 12^{2} = 36 + 64 + 100 + 144 = 344.Incorrect
Let the four numbers be x, x + 2, x + 4 and x + 6.
=> x + x + 2 + x + 4 + x + 6 = 36=> 4x + 12 = 36 => x = 6The numbers are 6, 8, 10 and 12.Sum of their squares = 6^{2} + 8^{2} + 10^{2} + 12^{2} = 36 + 64 + 100 + 144 = 344. 
Question 28 of 50
28. Question
Anil can do a work in 15 days while Sunil can do it in 25 days. How long will they take if both work together?
Correct
1/15 + 1/25 = 8/75
75/8 = 9 3/8 daysIncorrect
1/15 + 1/25 = 8/75
75/8 = 9 3/8 days 
Question 29 of 50
29. Question
A cistern has a leak which would empty the cistern in 20 minutes. A tap is turned on which admits 4 liters a minute into the cistern, and it is emptied in 24 minutes. How many liters does the cistern hold?
Correct
1/x – 1/20 = 1/24
x = 120
120 * 4 = 480Incorrect
1/x – 1/20 = 1/24
x = 120
120 * 4 = 480 
Question 30 of 50
30. Question
Three years ago the average age of a family of six members was 19 years. A boy have been born, the average age of the family is the same today. What is the age of the boy?
Correct
6 * 22 = 132
7 * 19 = 133
————–
1Incorrect
6 * 22 = 132
7 * 19 = 133
————–
1 
Question 31 of 50
31. Question
The average of the marks of 12 students in a class is 36. If the marks of each student are doubled, find the new average?
Correct
Sum of the marks for the 12 students = 12 * 36 = 432. The marks of each student are doubled, the sum also will be doubled.
The new sum = 432 * 2 = 864. So, the new average = 864/12 = 72.Incorrect
Sum of the marks for the 12 students = 12 * 36 = 432. The marks of each student are doubled, the sum also will be doubled.
The new sum = 432 * 2 = 864. So, the new average = 864/12 = 72. 
Question 32 of 50
32. Question
The ratio between the present ages of A and B is 5:3 respectively. The ratio between A’s age 4 years ago and B’s age 4 years hence is 1:1. What is the ratio between A’s age 4 years hence and B’s age 4 years ago?
Correct
Let the present ages of A and B be 5x and 3x years respectively.
Then, (5x – 4)/(3x + 4) = 1/1
2x = 8 => x = 4
Required ratio = (5x + 4):(3x – 4) = 24:8 = 3:1Incorrect
Let the present ages of A and B be 5x and 3x years respectively.
Then, (5x – 4)/(3x + 4) = 1/1
2x = 8 => x = 4
Required ratio = (5x + 4):(3x – 4) = 24:8 = 3:1 
Question 33 of 50
33. Question
A large tanker can be filled by two pipes A and B in 60 and 40 minutes respectively. How many minutes will it take to fill the tanker from empty state if B is used for half the time and A and B fill it together for the other half?
Correct
Part filled by (A + B) in 1 minute = (1/60 + 1/40) = 1/24
Suppose the tank is filled in x minutes.
Then, x/2(1/24 + 1/40) = 1
x/2 * 1/15 = 1 => x = 30 min.Incorrect
Part filled by (A + B) in 1 minute = (1/60 + 1/40) = 1/24
Suppose the tank is filled in x minutes.
Then, x/2(1/24 + 1/40) = 1
x/2 * 1/15 = 1 => x = 30 min. 
Question 34 of 50
34. Question
The probability that A speaks truth is 3/5 and that of B speaking truth is 4/7. What is the probability that they agree in stating the same fact?
Correct
If both agree stating the same fact, either both of them speak truth of both speak false.
Probability = 3/5 * 4/7 + 2/5 * 3/7
= 12/35 + 6/35 = 18/35Incorrect
If both agree stating the same fact, either both of them speak truth of both speak false.
Probability = 3/5 * 4/7 + 2/5 * 3/7
= 12/35 + 6/35 = 18/35 
Question 35 of 50
35. Question
If a man can cover 12 metres in one second, how many kilometres can he cover in 3 hours 45 minutes?
Correct
12 m/s = 12 * 18/5 kmph
3 hours 45 minutes = 3 3/4 hours = 15/4 hours
Distance = speed * time = 12 * 18/5 * 15/4 km = 162 km.Incorrect
12 m/s = 12 * 18/5 kmph
3 hours 45 minutes = 3 3/4 hours = 15/4 hours
Distance = speed * time = 12 * 18/5 * 15/4 km = 162 km. 
Question 36 of 50
36. Question
(24 * 5 * 7 * 9) / ? = 216
Correct
? = (24 * 5 * 7 * 9) / 216 = 35
Incorrect
? = (24 * 5 * 7 * 9) / 216 = 35

Question 37 of 50
37. Question
A can do a piece of work in 12 days. He worked for 15 days and then B completed the remaining work in 10 days. Both of them together will finish it in.
Correct
15/25 + 10/x = 1 => x = 25
1/25 + 1/25 = 2/25
25/2 = 12 1/2 daysIncorrect
15/25 + 10/x = 1 => x = 25
1/25 + 1/25 = 2/25
25/2 = 12 1/2 days 
Question 38 of 50
38. Question
LCM of 18 and 27 is:
Correct
Incorrect

Question 39 of 50
39. Question
Find the one which does not belong to that group ?
Correct
All are organs of our body which are in pairs except fingers.
Incorrect
All are organs of our body which are in pairs except fingers.

Question 40 of 50
40. Question
At an examination in which full marks were 500. A got 10% less than B, B got 25% more than C and C got 20% less than D. If A got 360marks, what percentage of full marks was obtained by D?
Correct
A B C D
90 100 80 100
A D
90 —– 100
360 —— ? = 400
500 —— 400
100 —— ? => 80%Incorrect
A B C D
90 100 80 100
A D
90 —– 100
360 —— ? = 400
500 —— 400
100 —— ? => 80% 
Question 41 of 50
41. Question
A box contains 3 blue marbles, 4 red, 6 green marbles and 2 yellow marbles. If three marbles are drawn what is the probability that one is yellow and two are red?
Correct
Given that there are three blue marbles, four red marbles, six green marbles and two yellow marbles.
When three marbles are drawn, the probability that one is yellow and two are red= (²C₁)(⁴C₂)/¹⁵C₃= (2 * 4 * 3 * 3 * 2)/(1 * 2 * 15 * 14 * 13) = 12/455Incorrect
Given that there are three blue marbles, four red marbles, six green marbles and two yellow marbles.
When three marbles are drawn, the probability that one is yellow and two are red= (²C₁)(⁴C₂)/¹⁵C₃= (2 * 4 * 3 * 3 * 2)/(1 * 2 * 15 * 14 * 13) = 12/455 
Question 42 of 50
42. Question
The C.P of 15 books is equal to the S.P of 18 books. Find his gain% or loss%?
Correct
15 CP = 18 SP
18 — 3 CP loss
100 — ? => 16 2/3% lossIncorrect
15 CP = 18 SP
18 — 3 CP loss
100 — ? => 16 2/3% loss 
Question 43 of 50
43. Question
A delegation of 5 members has to be formed from 3 ladies and 5 gentlemen. In how many ways the delegation can be formed, if 2 particular ladies are always included in the delegation?
Correct
There are three ladies and five gentlemen and a committee of 5 members to be formed.
Number of ways such that two ladies are always included in the committee = ⁶C₃ = (6 * 5 * 4)/6 = 20.Incorrect
There are three ladies and five gentlemen and a committee of 5 members to be formed.
Number of ways such that two ladies are always included in the committee = ⁶C₃ = (6 * 5 * 4)/6 = 20. 
Question 44 of 50
44. Question
Find the number of square tiles to cover the floor of a room measuring 4 m * 9 m leaving 0.25 m space around the room. A side of square tile is given to be 25 cms?
Correct
3 1/2 * 8 1/2 = 1/4 * 1/4 * x => x = 476
Incorrect
3 1/2 * 8 1/2 = 1/4 * 1/4 * x => x = 476

Question 45 of 50
45. Question
Divide Rs.32000 in the ratio 3:5?
Correct
3/8 * 32000 = 12000
5/8 * 32000 = 20000Incorrect
3/8 * 32000 = 12000
5/8 * 32000 = 20000 
Question 46 of 50
46. Question
If a + b + c = 0 and abc ≠ 0, then [X^{a3 / abc}][X^{b3 / abc}][X^{c3 / abc}] equals
Correct
X^{a3 / abc} * X^{b3 / abc} * X^{c3 / abc}
= X^{(a3 + b3 + c3) / abc}As a + b + c = 0, (a^{3} + b^{3} + c^{3}) / abc = 3The given expression equals X^{3}Incorrect
X^{a3 / abc} * X^{b3 / abc} * X^{c3 / abc}
= X^{(a3 + b3 + c3) / abc}As a + b + c = 0, (a^{3} + b^{3} + c^{3}) / abc = 3The given expression equals X^{3} 
Question 47 of 50
47. Question
Two pipes function simultaneously the reservoir will be filled in 12 hours. One pipe fills reservoir 10 hours faster than the other. How many hours does the faster pipe take to fill the reservoir?
Correct
1/x + 1/(x + 10) = 1/12
x = 20Incorrect
1/x + 1/(x + 10) = 1/12
x = 20 
Question 48 of 50
48. Question
The simple interest on Rs.12000 at a certain rate of interest in five years is Rs.7200. Find the compound interest on the same amount for five years at the same rate of interest.
Correct
R = 100 I / PT
=> R = (100 * 7200)/ (12000 * 5) = 12%CI = P{ [1 + R /100]^{n} – 1}= 12000 { [ 1 + 12 / 100]^{2} – 1} = Rs.3052.80Incorrect
R = 100 I / PT
=> R = (100 * 7200)/ (12000 * 5) = 12%CI = P{ [1 + R /100]^{n} – 1}= 12000 { [ 1 + 12 / 100]^{2} – 1} = Rs.3052.80 
Question 49 of 50
49. Question
A take twice as much time as B or thrice as much time to finish a piece of work. Working together, they can finish the work in 2 days. B can do the work alone in?
Correct
Suppose A, B and C take x, x/2 and x/3 respectively to finish the work.
Then, (1/x + 2/x + 3/x) = 1/2
6/x = 1/2 => x = 12
So, B takes 6 hours to finish the work.Incorrect
Suppose A, B and C take x, x/2 and x/3 respectively to finish the work.
Then, (1/x + 2/x + 3/x) = 1/2
6/x = 1/2 => x = 12
So, B takes 6 hours to finish the work. 
Question 50 of 50
50. Question
If the cost price of 50 articles is equal to the selling price of 40 articles, then the gain or loss percent is?
Correct
Given that, cost price of 50 article is equal to selling price of 40 articles.
Let cost price of one article = Rs. 1
Selling price of 40 articles = Rs. 50
But Cost price of 40 articles = Rs. 40
Therefore, the trader made profit.\Percentage of profit = 10/40 * 100 = 25%Incorrect
Given that, cost price of 50 article is equal to selling price of 40 articles.
Let cost price of one article = Rs. 1
Selling price of 40 articles = Rs. 50
But Cost price of 40 articles = Rs. 40
Therefore, the trader made profit.\Percentage of profit = 10/40 * 100 = 25%