Jenson had some blueberry biscuits and vanilla biscuits. He gave away 80 biscuits to his sister. 30% of them were blueberry biscuits and the rest were vanilla biscuits.

1. How many vanilla biscuits did he give his sister?
2. Jenson gave some blueberry biscuits to his cousin. ³₇ of all the biscuits he gave away to his sister and his cousin were blueberry biscuits. How many blueberry biscuits did he give his cousin?

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

Number of vanilla biscuits that Jenson gave to his sister
= 70% x 80
= ⁷⁰₁₀₀ x 80
= 56 

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

4 u = 56

1 u = 56 ÷ 4 = 14

Number of blueberry biscuits that Jenson gave to his sister and his cousin
= 3 u
= 3 x 14
= 42

Number of blueberry biscuits that Jenson gave to his sister
= 80 - 56
= 24

Number of blueberry biscuits that Jenson gave to his cousin
= 42 - 24
= 18

Answer(s): (a) 56; (b) 18