0
Q:

# Pipe A can fill the tank in 4 hours,while pipe B can fill it in 6 hours working separately.pipe C can empty whole the tank in 4 hours. He opened the pipe A and B simultaneously to fill the empty tank. He wanted to adjust his alarm so that he could open the pipe C when it was half-filled, but he mistakenly adjusted his alarm at a time when his tank would be 3/4th filled. what is the time difference between both the cases, to fill the tank fully:

 A) 48 min B) 54 min C) 30 min D) none of these

Answer:   B) 54 min

Explanation:

In ideal Case:

Time taken to fill the half tank by A and B = $\inline&space;\fn_jvn&space;\frac{50}{41.66}$ =$\inline&space;\fn_jvn&space;\frac{6}{5}$ hours

Time taken by A,B and C to fill rest half of the tank =$\inline&space;\fn_jvn&space;\frac{50}{16.66}$ = 3 hours

Total time = $\inline&space;\fn_jvn&space;\frac{6}{5}+3$ = 4 hours 12 min

In second case:

Time taken to fill $\inline&space;\fn_jvn&space;\frac{3}{4}$ tank by A and B =$\inline&space;\fn_jvn&space;\frac{75}{41.66}=\frac{9}{5}$ hours

Time taken by A,B and C to fill rest $\inline&space;\fn_jvn&space;\frac{1}{4}$ tank = $\inline&space;\fn_jvn&space;\frac{25}{16.66}=\frac{3}{2}$ hours

Total time =$\inline&space;\fn_jvn&space;\frac{9}{5}+\frac{3}{2}$ =3 hours 18 min

Therefore , difference in time = 54 minutes

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 & Explanation 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.

3 30
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

Answer & Explanation Answer: B) 26.6 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.

3 29
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

Answer & Explanation Answer: A) 50 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.

4 17
Q:

In a hostel, there was food for 1000 students for one month. After 10 days, 1000 more students joined the hostel. How long would the students be able to carry on with the remaining food?

 A) 10 days B) 15 days C) 20 days D) 5 days

Answer & Explanation Answer: A) 10 days

Explanation:

After 10 days, the remaining food would be sufficient for the 1000 students for 20 more days
$\fn_jvn&space;\small&space;\Rightarrow$ If 1000 more students are added, it shall be sufficient for only 10 days (as the no. of students is doubled, the days are halved).

6 83
Q:

Twenty men can do a work in eighteen days. Eighteen women can complete the same work in fifteen days. What is the ratio between the capacity of a woman and a man ?

 A) 4:5 B) 3:4 C) 4:3 D) 2:3

Explanation:

(20$\fn_jvn&space;\small&space;\times$18) men can complete the work in in one day.
one man's one day work = $\inline \fn_jvn \small \frac{1}{360}$
(18$\fn_jvn&space;\small&space;\times$15) women can complete the work in 1 day
1 woman's one day work = $\inline \fn_jvn \small \frac{1}{270}$
So, required ratio = $\inline \fn_jvn \small \frac{1}{270} :\frac{1}{360}$ = 4:3