Michael had some vanilla biscuits and banana biscuits. He gave away 200 biscuits to his brother. 30% of them were vanilla biscuits and the rest were banana biscuits.

1. How many banana biscuits did he give his brother?
2. Michael gave some vanilla biscuits to his sister. ³₇ of all the biscuits he gave away to his brother and his sister were vanilla biscuits. How many vanilla biscuits did he give his sister?

(a)
Percentage of banana biscuits
= 100% - 30%
= 70%

Number of banana biscuits that Michael gave to his brother
= 70% x 200
= ⁷⁰₁₀₀ x 200
= 140 

(b)
Fraction of all the biscuits he gave away to his brother and his sister that were banana biscuits
= 1 - ³₇
= ⁴₇

4 u = 140

1 u = 140 ÷ 4 = 35

Number of vanilla biscuits that Michael gave to his brother and his sister
= 3 u
= 3 x 35
= 105

Number of vanilla biscuits that Michael gave to his brother
= 200 - 140
= 60

Number of vanilla biscuits that Michael gave to his sister
= 105 - 60
= 45

Answer(s): (a) 140; (b) 45