Answer:
Josh should add 1/4 cup of yellow paint to each cup of red paint to make the shade of orange.
Explanation:
If there is supposed to be 4 parts of red paint to every 1 part of yellow paint, you would divide one cup of red paint into four parts. That gives you 1/4 which means that one part is equal to 1/4 cup. So four parts of 1/4 cups gives you 1 cup of red paint and one part of 1/4 cups gives 1/4 cup of yellow paint.
1/4 cup of yellow to every 1 cup of red.