Answer:
x = 3/7
Step-by-step explanation:
Red paint : White paint = 3 cups : 7 cups
How many cups of red paint should be added to 1 cup of white paint
Red paint : White paint = x cups : 1 cup
Equate the ratios
3 cups : 7 cups = x cups : 1 cup
3 / 7 = x / 1
Cross product
3 * 1 = 7 * x
3 = 7x
Divide both sides by 7
x = 3 / 7
Number of cups of cups of red paint that should be added to 1 cup of white paint is 3/7
I did this by representing the unknown number of cups of red paint with x and equating the two ratios