Troy had 1/4 as many blocks as Doug. When Doug gave half of his blocks to Troy, he then had 5 fewer blocks than his friend. How many blocks did Doug have at first?
D = 4T
D/2 = 4T/2 = T + 5
Solve for T, then D
D/2 = 4T/2 = T + 5
Solve for T, then D