Luis had some chocolate chip cupcakes and apricot cupcakes. He gave away 115 cupcakes to his cousin. 20% of them were chocolate chip cupcakes and the rest were apricot cupcakes.

1. How many apricot cupcakes did he give his cousin?
2. Luis gave some chocolate chip cupcakes to his sister. ³₇ of all the cupcakes he gave away to his cousin and his sister were chocolate chip cupcakes. How many chocolate chip cupcakes did he give his sister?

(a)
Percentage of apricot cupcakes
= 100% - 20%
= 80%

Number of apricot cupcakes that Luis gave to his cousin
= 80% x 115
= ⁸⁰₁₀₀ x 115
= 92 

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

4 u = 92

1 u = 92 ÷ 4 = 23

Number of chocolate chip cupcakes that Luis gave to his cousin and his sister
= 3 u
= 3 x 23
= 69

Number of chocolate chip cupcakes that Luis gave to his cousin
= 115 - 92
= 23

Number of chocolate chip cupcakes that Luis gave to his sister
= 69 - 23
= 46

Answer(s): (a) 92; (b) 46