Question 1010607
30 minutes = 0.5 hours



The idea is to form a proportion and then isolate the variable.



(2 birdhouses)/(0.5 hours) = (x birdhouses)/(4 hours)



2/0.5 = x/4



2*4 = 0.5*x ... cross multiply



8 = 0.5x



0.5x = 8



0.5x/0.5 = 8/0.5 ... divide both sides by 0.5



x = 16



He can make 16 birdhouses.