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:

There is sufficient salary to give K for 10 days and L for 15 days. Then how many days will the money last if both has to be given the salary ?

 A) 6 days B) 12 days C) 4 days D) 9 days

Explanation:

K's 1 day's salary = 1/10
L's 1 day's salary = 1/15
Together their 1 day's salary = 1/10 + 1/15
= 3/30 + 2/30
= 5/30
= 1/6
So the money will be
enough for paying them both for 6 days.

1 119
Q:

4 men can repair a road in 7 hours. How many men are required to repair the road in 2 hours ?

 A) 17 men B) 14 men C) 13 men D) 16 men

Explanation:

M x T / W = Constant
where, M= Men (no. of men)
T= Time taken
So, here we apply
M1 x T1/ W1 = M2 x T2 / W2
Given that, M1 = 4 men, T1 = 7 hours ; T2 = 2 hours, we have to find M2 =?
Note that here, W1 = W2 = 1 road, ie. equal work load.
Clearly, substituting in the above equation we get, M2 = 14 men.

2 250
Q:

If 6 engines consume 24 metric tonnes of coal, when each is working 8 hours day, how much coal will be required for 9 engines, each running 13hours a day, it being given that 2 engines of former type consume as much as 3 engines of latter type ?

 A) 45 metric tonnes B) 47 metric tonnes C) 55 metric tonnes D) 34 metric tonnes

Explanation:

2 engines of former type for one hour consumes 2x24/(6x8) = 1 metric ton
i.e. 3 engines of latter type consumes 1 ton for one hour
hence 9 engines consumes 3 tons for one hour
for 15 hours it is 15 x 3 = 45 metric tonnes.

1 171
Q:

A does half as much work as Band C does half as much work as A and B together. If C alone can finish the work in 40 days, then together ,all will finish the work in  ?

 A) 17 + 4/7 days B) 13 + 1/3 days C) 15 + 3/2 days D) 16 days

Explanation:

C alone can finish the work in 40 days.
As given C does half as much work as A and B together
=> (A + B) can do it in 20 days
(A + B)s 1 days wok = 1/20.
A's 1 days work : B's 1 days Work = 1/2 : 1 = 1:2(given)
A's 1 day’s work = (1/20) x (1/3) = (1/60) [Divide 1/20 in the raio 1:2]
B's 1 days work = (1/20) x (2/3) = 1/30
(A+B+C)'s 1 day's work = (1/60) + (1/30) + (1/40) = 9/120 = 3/40

All the three together will finish it in 40/3 = 13 and 1/3 days.

3 263
Q:

An air conditioner can coo the hall in 40 miutes while another takes 45 minutes to cool under similar conditions. If both air conditioners are switched on at same instance then how long will it take to cool the room approximately ?

 A) 18 minutes B) 19 minutes C) 22 minutes D) 24 minutes

Explanation:

Let the two conditioners be A and B

'A' cools at 40min

'B' at 45min

Together =(axb)/(a+b) = (45x40)/85 = 21.1764 = (approx) 22 min.