how many cups of blue paint will Nathaniel use with 1 cup of red paint?

Question

Nathaniel uses 1/5 cup of blue paint for every 2/5 cup of red paint to make purple paint.

Answer 1

1/5 blue             ?

--------- =  --------------

2/5 red          1 red

 

1/5 * 1 = 2/5 * ?

 

1/5 = 2/5 * ?

 

1 = 2 * ?

 

? = 1/2 

 

1/2 cup of blue