Tim had some chocolate chip tarts and cranberry tarts. He gave away 90 tarts to his cousin. 40% of them were chocolate chip tarts and the rest were cranberry tarts.

1. How many cranberry tarts did he give his cousin?
2. Tim gave some chocolate chip tarts to his sister. ³₅ of all the tarts he gave away to his cousin and his sister were chocolate chip tarts. How many chocolate chip tarts did he give his sister?

(a)
Percentage of cranberry tarts
= 100% - 40%
= 60%

Number of cranberry tarts that Tim gave to his cousin
= 60% x 90
= ⁶⁰₁₀₀ x 90
= 54 

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

2 u = 54

1 u = 54 ÷ 2 = 27

Number of chocolate chip tarts that Tim gave to his cousin and his sister
= 3 u
= 3 x 27
= 81

Number of chocolate chip tarts that Tim gave to his cousin
= 90 - 54
= 36

Number of chocolate chip tarts that Tim gave to his sister
= 81 - 36
= 45

Answer(s): (a) 54; (b) 45