Question

A and b can build a wall in 15 hours and 20 hours respectively. if they worked together they use 180 less bricks per hour and build the wall in 12 hours. find the number of bricks in the wall

Answer 1

Dear Student,
Assume there are in total x bricks.
So, according to questoins , A will use x/15 bricks per hour and B will use x/20 bricks per hour.
Now we they work together, number of bricks per hour used by them will be (x/15+x/20 – 180) and these we can say that for 12 hours of work,
(x/15+x/20 – 180) * 12 = x.
Use these equation to find x.