Problema Solution
Mr. Joe has 45 20-cent and 31-cent stamps all told. The stamps are worth $12.19. How many of each kind of stamp does he have?
Answer provided by our tutors
let 'x' represent the number of 20-cent stamps, then '45-x' represents the number of 31-cent stamps and we have:
12.19 = 0.2x + 0.31(45-x)
solving for 'x' we have x=16
45-16 = 29
there were 16 20-cent stamps and 29 31-cent stamps