A can lay a railway track between two given stations in 16 days and B can do the same job in 12 days. With help of C, they did the job in 4 days only. Then, C alone can do the job in ?
A.
4
B.
9.6
C.
9
D.
10
Answer: Option B
Explanation:
Part of work completed by A and B in 4 days = 4*((1/16) + (1/12)) = 7/12 C can complete 5/12th of the work in 4 days C can complete the whole job in 4÷(5/12) = 9.6 days
If 10 bulls can plough 20 identical fields in 3 days working 10 hours a day, then in how many days can 30 bulls plough 32 same identical fields working 8 hours a day?
A.
2
B.
4
C.
5
D.
7
Answer: Option A
Explanation:
M1*D1*W2 = M2*D2*W1 10*3*10*32 = 30*d*8*20 d = 2 days
A work can be finished in 16 days by twenty women. The same work can be finished in fifteen days by sixteen men. The ratio between the capacity of a man and a woman is ?
A.
1:3
B.
4:3
C.
2:3
D.
2:1
Answer: Option B
Explanation:
Work done by 20 women in 1 day = 1/16
Work done by 1 woman in 1 day = 1/(16×20) Work done by 16 men in 1 day = 1/15
Work done by 1 man in 1 day = 1/(15×16) Ratio of the capacity of a man and woman =1/(15×16) : 1/(16×20) = 1/15 : 1/20
P, Q and R can complete a work in 24, 6 and 12 days respectively. The work will be completed in days if all of them are working together ?
A.
2
B.
3 3â„7
C.
4 ¼
D.
5
Answer: Option B
Explanation:
Work done by P in 1 day = 1/24 Work done by Q in 1 day = 1/6 Work done by R in 1 day = 1/12 Work done by P,Q and R in 1 day = 1/24 + 1/6 + 1/12 = 7/24 => Working together, they will complete the work in 24/7 days = 3 3⁄7 days
Two pipes P and Q can fill a cistern in 12 minutes and 16 minutes respectively. Simultaneously both the pipes are opened together, then after how much time Q should be closed so that the tank is full in 9 min ?
A.
2 min
B.
3 min
C.
4 min
D.
5 min
Answer: Option C
Explanation:
Let Q be closed after x min.
Then part filled by (P+Q) in x min + part filled by P in ( 9 – x )min
