8
Q:

# Adam and Smith are working on a project. Adam takes 6 hrs to type 36 pages on a computer, while Smith takes 5 hrs to type 40 pages. How much time will they take, working together on two different computers to type a project of 120 pages?

 A) 8 hrs 45 min B) 8 hrs 42 min C) 8 hrs D) 8 hrs 34 min

Answer:   D) 8 hrs 34 min

Explanation:

Number of pages typed by Adam in 1 hour = $\inline \fn_jvn \small \frac{36}{6}$ = 6
Number of pages typed by Smith in 1 hour = $\inline \fn_jvn \small \frac{40}{5}$ = 8
Number of pages typed by both in 1 hour = (6 + 8) = 14
Time taken by both to type 110 pages = (120 * 1/14) = 8 $\inline \fn_jvn \small \frac{4}{7}$ = 8 hrs 34 min.

Q:

K, L and M can do a piece of work in 20, 30 and 60 days respectively. In how many days can K do the total work if he is assisted by L and M on every third day ?

 A) 15 days B) 13 days C) 12 days D) 10 days

Explanation:

In one day work done by K = 1/20
Work done by K in 2 days = 1/10
Work done by K,L,M on 3rd day =1/20 + 1/30 + 1/60 = 1/10
Therefore, workdone in 3 days is = 1/10 + 1/10 = 1/5
1/5th of the work will be completed at the end of 3 days.
The remaining work = 1 - 1/5 = 4/5
1/5 of work is completed in 3 days
Total work wiil be done in 3 x 5 = 15 days.

3 77
Q:

A shopkeeper has a job to print certain number of documents and there are three machines P, Q and R for this job. P can complete the job in 3 days, Q can complete the job in 4 days and R can complete the job in 6 days. How many days the shopkeeper will it take to complete the job if all the machines are used simultaneously ?

 A) 4/3 days B) 2 days C) 3/2 days D) 4 days

Explanation:

Let the total number of documents to be printed be 12.
The number of documents printed by P in 1 day = 4.
The number of documents printed by Q in 1 day = 3.
The number of documents printed by R in 1 day = 2.
Thus, the total number of documents that can be printed by all the machines working simultaneously in a single day = 9.
Therefore, the number of days taken to complete the whole work = 12/9 = 4/3 days.

4 81
Q:

Twelve children take sixteen days to complete a work which can be completed by 8 adults in 12 days. After working for 3 days, sixteen adults left and six adults and four children joined them. How many days will they take to complete the remaining work ?

 A) 3 days B) 2 days C) 6 days D) 12 days

Explanation:

From the given data,
12 children 16 days work,
One child’s one day work = 1/192.
One adult’s one day’s work = 1/96.
Work done in 3 days = ((1/96) x 16 x 3) = 1/2
Remaining work = 1 – 1/2 = 1/2
(6 adults+ 4 children)’s 1 day’s work = 6/96 + 4/192 = 1/12
1/12 work is done by them in 1 day.
1/2 work is done by them in 12 x (1/2) = 6 days.

4 115
Q:

After working for 8 days, Arun finds that only $\inline \fn_jvn \small \frac{1}{3}$ rd of the work has been done. He employs Akhil who is 60% as efficient as Arun. How many days more would Akhil take to complete the work?

 A) 24.5 days B) 26.6 days C) 25 days D) 20 days

Explanation:

Arun has completed $\inline \fn_jvn \small \frac{1}{3}$ rd of the work in 8 days
Then he can complete the total work in
$\inline \fn_jvn \small \frac{1}{3}$ ---- 8
1 ---- ?
= 24 days
But given Akhil is only 60% as efficient as Arun
Akhil = $\inline \fn_jvn \small \frac{1}{24}\times \frac{60}{100}=\frac{1}{40}$
Akhil can complete the total work in 40 days
Now, remaining 2/3rd of work can be completed in
1 ------   40
$\inline \fn_jvn \small \frac{2}{3}$  ------   ?   $\fn_jvn&space;\small&space;\Rightarrow$ 26.66 days.

8 236
Q:

50 men can build a tank in 40days, but though they begin the work together, 5 men quit every ten days. The time needed to build the tank is ?

 A) 50 days B) 48 days C) 47.5 days D) 49 days

Explanation:

50 men can build a tank in 40 days
Assume 1 man does 1 unit of work in 1 day
Then the total work is 50×40 = 2000 units

50 men work in the first 10 days and completes 50×10 = 500 units of work
45 men work in the next 10 days and completes 45×10 = 450 units of work
40 men work in the next 10 days and completes 40×10 = 400 units of work
35 men work in the next 10 days and completes 35×10 = 350 units of work
So far 500 + 450 + 400 + 350 = 1700 units of work is completed and

remaining work is 2000 - 1700 = 300 units

30 men work in the next 10 days. In each day, they does 30 units of work.

Therefore, additional days required = $\inline \fn_jvn \small \frac{300}{30}=10$

Thus, total 10+10+10+10+10 = 50 days required.