Lee had some cranberry biscuits and chocolate chip biscuits. He gave away 110 biscuits to his cousin. 10% of them were cranberry biscuits and the rest were chocolate chip biscuits.

1. How many chocolate chip biscuits did he give his cousin?
2. Lee gave some cranberry biscuits to his sister. ²₅ of all the biscuits he gave away to his cousin and his sister were cranberry biscuits. How many cranberry biscuits did he give his sister?

(a)
Percentage of chocolate chip biscuits
= 100% - 10%
= 90%

Number of chocolate chip biscuits that Lee gave to his cousin
= 90% x 110
= ⁹⁰₁₀₀ x 110
= 99 

(b)
Fraction of all the biscuits he gave away to his cousin and his sister that were chocolate chip biscuits
= 1 - ²₅
= ³₅

3 u = 99

1 u = 99 ÷ 3 = 33

Number of cranberry biscuits that Lee gave to his cousin and his sister
= 2 u
= 2 x 33
= 66

Number of cranberry biscuits that Lee gave to his cousin
= 110 - 99
= 11

Number of cranberry biscuits that Lee gave to his sister
= 66 - 11
= 55

Answer(s): (a) 99; (b) 55