Bobby had some banana wafers and blueberry wafers. He gave away 100 wafers to his brother. 20% of them were banana wafers and the rest were blueberry wafers.

1. How many blueberry wafers did he give his brother?
2. Bobby gave some banana wafers to his cousin. ⁵₇ of all the wafers he gave away to his brother and his cousin were banana wafers. How many banana wafers did he give his cousin?

(a)
Percentage of blueberry wafers
= 100% - 20%
= 80%

Number of blueberry wafers that Bobby gave to his brother
= 80% x 100
= ⁸⁰₁₀₀ x 100
= 80 

(b)
Fraction of all the wafers he gave away to his brother and his cousin that were blueberry wafers
= 1 - ⁵₇
= ²₇

2 u = 80

1 u = 80 ÷ 2 = 40

Number of banana wafers that Bobby gave to his brother and his cousin
= 5 u
= 5 x 40
= 200

Number of banana wafers that Bobby gave to his brother
= 100 - 80
= 20

Number of banana wafers that Bobby gave to his cousin
= 200 - 20
= 180

Answer(s): (a) 80; (b) 180