Question

If it takes 3 days for 10 workers to finish building one house, how many days will it take 15 workers to finish 4 houses?

Answer 1

a = house
3 days x 10 worker = a
a = 30 work unit
4a = 120 work unit
120 work unit = 15 workers * y days
y = 120/15 = 8 days

i hope this isn't too confusing