74.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, the time taken by 15 men and 20 boys in doing the same type of work will be:
A. 4 days
B. 5 days
C. 6 days
D. 7 days
Answer:
Option : A
Let 1 man's 1 day's work = x and 1 boy's 1 day's work = y.
|
Then, 6x + 8y =
|
1
|
and 26x + 48y =
|
1
|
10
|
2
|
Solving these two equations, we get : x =
|
1
|
and y =
|
1
|
100
|
200
|
(15 men + 20 boy)'s 1 day's work =
|
|
15
|
+
|
20
|
|
=
|
1
|
100
|
200
|
4
|
∴ 15 men and 20 boys can do the work in 4 days.
|
