Q1. Carpenter A builds furniture in 15 days, and Carpenter B does the same task in 10 days. In how many days, will they complete the job if working together?
A. 9 days
B. 6 days
C. 8 days
D. 5 days
Answer Option B
Explanation
A's 1 day's work =
1
15
B's 1 day's work =
1
10
(A + B)'s 1 day's work =
1
15
+
1
10
=
1
6
=> Both of them will complete the job in 6 days.
Q2. Mohan, Rohan, and Sohan can complete a task in 12, 6, and 24 days respectively. If they work together, in how many days will they complete the work?
A.
1
24
day
B.
24
7
days
C. 4 days
D.
7
24
day
Answer Option B
Explanation
Mohan's 1 day's work =
1
12
Rohan's 1 day's work =
1
6
Sohan's 1 day's work =
1
24
(Moahn + Rohan + Sohan)'s 1 day's work =
1
12
+
1
6
+
1
24
=
7
24
=> All of them will complete the job in
24
7
days
Q3. Painter A can paint a house in 16 days, and painter B can do the same work in 20 days. With the help of painter C, they paint the house in 8 days only. Then, Painter C alone can do this task in
A. 80 days
B. 85 days
C. 79 days
D. 76 days
Answer Option A
Explanation
A's 1 day's work =
1
16
B's 1 day's work =
1
20
(A + B + C)'s 1 day's work =
1
10
=> C's 1 day's work =
1
10

1
16
+
1
20
=
1
80
So, C can paint the house in 80 days.
Q4. 10 girls can complete a piece of work in 8 days and 8 boys take 20 days to complete the same task. How many days will 5 girls and 10 boys take to finish this job?
A. 8 days
B. 9 days
C. 7 days
D. 10 days
Answer Option A
Explanation
1 girl's 1 day's work =
1
80
1 boy's 1 day's work =
1
160
(5 girls + 10 boys)'s 1 day's work =
5 x
1
80
+
10 x
1
160
=
1
8
=> 5 girls and 10 boys will complete the work in 8 days.
Q5. A tank has two leakages. The first leakage alone can empty the tank in 9 minutes and the second alone would have done it in 6 minutes. If water leaks out at a costant rate, how long does it take both the leakage together to empty the tank?
A. 3.1 min
B. 3.6 min
C. 3.5 min
D. 4 min
Answer Option B
Explanation
1 minute's work of both the leakage =
1
9
+
1
6
=
5
18
So, both the leakage will empty the tank in
18
5
min
Q6. Ankit and Arya together can finish a task in 4 days. If Ankit alone, can do the same task in 12 days. In how many days, Arya alone can complete this work?
A. 4 days
B. 5 days
C. 7 days
D. 6 days
Answer Option D
Explanation
(Ankit + Arya)'s 1 day work =
1
4
(Ankit)'s 1 day work =
1
12
(Arya)'s 1 day work =
1
4

1
12
=
1
6
Hence, Arya can complete the work in 6 days
Q7. Two men and three women can repair a bridge in 10 days while three men and two women can do same work in 8 days. If two men and one woman are used to finish this work, in how many days they will complete it?
A. 15 days
B. 12.5 days
C. 13.5 days
D. 11 days
Answer Option B
Explanation
Let 1 man's 1 day's work = x and 1 woman's day's work = y. Then, 2x + 3y =
1
10
and 3x + 2y =
1
8
(2 men and 1 woman)'s 1 day's work =
2 *
7
200
+ 1 *
1
100
=
2
25
So, 2 men and 1 woman together can finish the work in