7
Q:

# K can build a wall in 30 days. L can demolish that wall in 60 days. If K and L work on alternate days, when will the wall be completed ?

 A) 120 days B) 119 days C) 118 days D) 117 days

Explanation:

K's work in a day(1st day) = 1/30
L's work in a day(2nd day)= -1/60(demolishing)
hence in 2 days, combined work= 1/30 - 1/60 =1/60
since both works alternatively, K will work in odd days and L will work in even days.
1/60 unit work is done in 2 days
58/60 unit work will be done in 2 x 58 days = 116 days
Remaining work = 1-58/60 = 1/30
Next day, it will be K's turn and K will finish the remaining 1/30 work.
hence total days = 116 + 1 = 117.

Q:

Two persons Shyam and Rahim can do a job in 32 days together. Rahim can do the same job in 48 days alone. They started working together and after working 8 days Rahim is replaced by a third person Ram whose efficiency is half that of Rahim. Find in how many days the remaining work will be completed by both Shyam and Ram together?

 A) 16 days B) 72/5 days C) 15 days D) 96/5 days

Explanation:

Work done by Shyam and Rahim in 8 days = 8/32 = 1/4

Remaining work to be done by Shyam and Ram = 1 - 1/4 = 3/4

Given efficieny of Ram is half of Rahim i.e, as Rahim can do the work in 48 days, Ram can do the work in 24 days.

One day work of Ram and Shyam = (1/32 - 1/48) + 1/24 = 5/96

Hence, the total work can be done by Shyam and Ram together in 96/5 days.

Therefore, remaining work 3/4 can be done by them in 3/4 x 96/5 = 72/5 = 14.4 days.

0 22
Q:

6 men can complete a piece of work in 12 days. 8 women can complete the same piece of work in 18 days whereas 18 children can complete the piece of work in 10 days. 4 men, 12 women and 20 children work together for 2 days. If only men were to complete the remaining work in 1 day how many men would be required totally?

 A) 38 B) 72 C) 36 D) 76

Explanation:

Given 4men, 12 women and 20 children work for  2 days.

Workdone for 2 days by 4men, 12 women and 20 children =

Therefore, remaining work = 1 - $\frac{1}{2}$ = $\frac{1}{2}$

To complete the same work by only men in 1 day,

We know that M1 x D1 = M2 x D2

Here M1 = 6 , D1 = 12 and M2 = M , D2 = 1

12 x 6 = M x 1

=> M = 12 x 6 = 72

=> But the remaining work = 1/2

Men required => 1/2 x 72 = 36

Only men required to Complete the remaining work in 1 day = 36.

7 341
Q:

Three men, four women and six children can complete a work in 9 days. A women does  double the work a man does and a child does half the work a man does. How many women alone can complete this work in 9 days?

 A) 7 B) 8 C) 9 D) 6

Explanation:

Given (3 Men + 4 Women + 6 Children) -----> 9 days

But W = 2M and C = M/2

Now, convert Men and Children into Women by

Therefore, 7 women alone can complete this work in 9 days.

6 320
Q:

9 girls working 7 hours a day can complete a piece of work in 15 day. In how many days can 6 girls working for 9 hours a day, complete the same piece of work?

 A) 35/4 days B) 17.5 days C) 19 3/4 days D) 37/3 days

Explanation:

Let the number of days be 'p'

As the work is same, we know that

Where M = Men, D = Days, H = Hours per day

Here M1 = 9, D1 = 15, H1 = 7

M2 = 6, D2 = p, H2 = 9

=> 9 x 15 x 7 = 6 x p x 9

=> p = 35/2 = 17.5 days.

6 560
Q:

If a soldier fires 7 shots from a gun in 12 minutes then find the total number of shots fired by the man in 3/2 hrs.

 A) 45 B) 44 C) 46 D) 47

Explanation:

Here given soldier shots 7 shots in 12 min

=> 1 shot doen't take any time in 12 min

=> Only 6 shots take 12 min

12 min ------ 6 shots

90 min ------ ? shots

=> 90 x (6/12) = 45

Therefore, total shots fired in 90 minutes = 45 + 1 = 46 shots.

6 321
Q:

A woman fills a bucket in 6 minutes. 1845 buckets have to be filled from 8 am. to 9:30 am. How many woman employees should be employed for this task?

 A) 111 B) 117 C) 123 D) 139

Explanation:

We know that,

Here M1 = 1, D1 = 6 min, W1 = 1 and M2 = M, D2 = 90 min, W2 = 1845

=> M = 123

7 439
Q:

If 6 men and 8 boys can do a piece of work in 10 days while 26 men and 48 boys can do the same in 2 days what is time taken by 15 men and 20 boys?

 A) 4 days B) 6 days C) 7 days D) 5 days

Explanation:

Given that

6 men and 8 boys can do a piece of work in 10 days

26 men and 48 boys can do the same in 2 days

As the work done is equal,

10(6M + 8B) = 2(26M + 48B)

60M + 80B = 52M + 96B

=> M = 2B

=> B = M/2 ……(1)

Now Put (1) in 15M + 20B

=> 15M + 10M = 25M

Now, 6M + 8B in 10 days

=> (6M + 4M) 10 = 100M

Then D(25M) = 100M

=> D = 4 days.

8 543
Q:

A certain job was assigned to a group of women to do it in 20 days. But 12 women did not turn up for the job and the remaining did the job in 32 days. The original number of women in the group was?

 A) 36 B) 32 C) 22 D) 28

Explanation:

Let the total women in the group be 'W'

Then according to the given data,

W x 20 = (W-12) x 32

=> W = 32

Therefore, the total number of women in the group = 32