Alvin is selling his marble set. He has 100 marbles. 20% are white, 30% are black, and the rest are different colors. He sells the white ones for a nickel each, the black ones for a dime each, and the colors for $0.20 each. How much does he earn? Give me reasons, before answering the question
He has 20 white marbles because 100 x .2 = 20. He has 30 black marbles because 100 x .3 = 30. He has 50 color marbles because 100 - 20 - 30 = 50. He earns $1 from white marbles because 20 x .05 = 1. He earns $3 from the black marbles because 30 x .1 = 3. He earns $10 from the colors because 50 x .2 = 10. He earns $14 in total because 1 + 3 + 10 = 14. So the final answer is 14.