There are 500 students in a local high school. 40 percent are juniors. 70 percent of juniors are involved in sports. How many juniors are involved in sports? Give the rationale and then the answer.
Let's think step by step. Juniors:500(.40) = 200. Juniors in sports:200(.70) = 140 students.. The answer is: 140.

Carlos has some gold quarters. If he spends them in a store, they are worth the regular amount. If he melts them down, he can get $100 per ounce. Each quarter weighs 1/5 of an ounce. How many times more money would he get from melting them down instead of spending them in a store? Give the rationale and then the answer.
Let's think step by step. If he melts them down, five quarters equals $100 because 1 / (1 / 5) = 5. If he spends those five quarters they are worth $1.25 because 5 x .25 = 1.25. They are worth 80 times more melted down because 100 / 1.25 = 80.. The answer is: 80.

Jeremy's uncle gave him $50 to spend on basketball equipment. He bought 5 jerseys that cost $2 each, a basketball that cost $18, and a pair of shorts that cost $8. How much money does Jeremy have left? Give the rationale and then the answer.
Let's think step by step. The cost of the jerseys is 5 jerseys $2 / jersey = $10. The total cost of the jerseys, the basketball, and the shorts is $10 + $18 + $8 = $36. Jeremy has $50 - $36 = $14 left.. The answer is: 14.