Oliver had some cherry cookies and cranberry cookies. He gave away 100 cookies to his brother. 25% of them were cherry cookies and the rest were cranberry cookies.

1. How many cranberry cookies did he give his brother?
2. Oliver gave some cherry cookies to his sister. ⁴₇ of all the cookies he gave away to his brother and his sister were cherry cookies. How many cherry cookies did he give his sister?

(a)
Percentage of cranberry cookies
= 100% - 25%
= 75%

Number of cranberry cookies that Oliver gave to his brother
= 75% x 100
= ⁷⁵₁₀₀ x 100
= 75 

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

3 u = 75

1 u = 75 ÷ 3 = 25

Number of cherry cookies that Oliver gave to his brother and his sister
= 4 u
= 4 x 25
= 100

Number of cherry cookies that Oliver gave to his brother
= 100 - 75
= 25

Number of cherry cookies that Oliver gave to his sister
= 100 - 25
= 75

Answer(s): (a) 75; (b) 75