Wilma has a garden with 3 types of flowers. The garden has 6 rows, with 13 flowers in each row. Wilma has 12 yellow flowers, two times more green flowers, and the rest consist of red flowers. How many red flowers does Wilma have? Give the rationale and then the answer.
Let's think step by step. The garden has space for 6 * 13 = 78 flowers in total. Wilma has two times more green flowers than yellow flowers, which means she has 2 * 12 = 24 green flowers. That leaves us with 78 - 24 - 12 = 42 red flowers in the garden.. The answer is: 42.

Piazzanos Pizzeria has a buy-1-get-1-free special on triple cheese pizzas, and a buy-2-get-1-free special on meat lovers pizzas. If the standard price for a pizza is $5, how much does it cost, in dollars, to purchase 10 triple cheese and 9 meat lovers pizzas using the special pricing? Give the rationale and then the answer.
Let's think step by step. Using buy - 1 - get - 1 - free pricing, it costs 1 * $5 = $5 to buy 2 triple cheese pizzas. At $5 per 2 pizzas, it costs $5 / 2 = $2.5 per triple cheese pizza. Using buy - 2 - get - 1 - free pricing, it costs 2 * $5 = $10 to buy 3 meat lovers pizzas. At $10 per three pizzas, it cost $10 / 3 = $3 and $1 / 3 per meat lovers pizza. With the buy - 1 - get - 1 - free pricing, 10 triple cheese pizzas are 10 * $2.5 = $25. With the buy - 2 - get - 1 - free pricing, 9 meat lovers pizzas are 9 * ($3 + $1 / 3) = $30. In total, for 10 triple cheese and 9 meat lovers pizzas, it will cost $25 + $30 = $55.. The answer is: 55.

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 the rationale and then the answer.
Let's think step by step. 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.. The answer is: 14.