Answer:
How long will it take them to do the work together? A. 6 days
the boy does 1/15 of the work per day
father does 1/10 of the work per day
together they do 1/15+1/10 = (2+3)/30=5/30 =1/6
To know how long it will take them to complete the work together, this fraction must be reversed = 6
it takes 6 days
Explanation: