Question

4 boys and 6 girls can do a job in78 days. How many days will 7 boys and 8 girls can do it

Answer 1

Let the no. of days required by a boy = x
Let the no. Of days required by a girl = y



Therefore, boy's one day work = 1/x
And girl's one day work = 1/ y

ATQ,
78(4/X + 6/Y)= 1
4/X + 6/Y =1/78 - EQ1

SO, 7/X +8/Y=1 - EQ 2

HOPE IT HELPS...
MARK AS BRAINLIEST.