Find the cost per ounce of a sunscreen made from 150 oz of lotion that cost $3.43 per ounce and 50 oz of lotion that cost $10.47 per ounce.

Question

 Find the cost.

Answer 1

150(3.43) + 50(10.47) = 200X

514.5 + 523.5 = 1038 = 200X

X = 1038/200 = $5.19 per ounce

5.19 is within 5.28 of 10.47

5.19 is within 1.76 of 3.43

1.76 x 3 = 5.28

50 x 3 = 150

you need 3 times more of 3.43 than of 10.47