A store sells pencils and erasers. It has a rule that for every pencil you buy, you must buy 2 erasers which cost 1/2 the price of the pencils. If they sold 20 pencils and earned $80, how much do erasers cost?
Let's think: They sold 40 erasers because 20 x 2 = 40. Therefore 20(Pencil Price) + (1 / 2)(40 x Pencil Price) = 80. Therefore 40(Pencil Price) = 80. Therefore (Pencil Price) equals 2 because 80 / 40 = 2. An eraser costs $1 because 2 / 2 = 1.. The answer is: 1.

Tom was putting hardwood flooring into his living room that measured 16' long and 20' wide. The flooring comes 10 sq ft per box and he has already put down 250 sq ft of flooring. How many more boxes does Tom need to complete the job?
Let's think: The entire sq ft of the living room is LxW so the room is 16x20 = 320 sq ft. Tom has already put down 250 sq ft so he needs to put down 320 - 250 = 70 sq ft of flooring. The boxes contain 10 sq ft of flooring per box and he needs 70 more sq ft of flooring so he needs 70 / 10 = 7 more boxes.. The answer is: 7.

Sally, Sam, and Steve went to play with their marbles. In the beginning, Sam has twice as many marbles as Steve while Sally has 5 less than Sam. After Sam has given Sally and Steve 3 marbles each, Sam has 8 marbles left. How many marbles does Steve have now?
Let's think: Sam has 8 marbles left after giving 3 marbles / person x 2 people = 6 marbles to Sally and Steve. Hence, Sam had 8 marbles + 6 marbles = 14 marbles in the beginning. Sam had twice as many marbles as Steve, therefore Steve has 14 marbles / 2 = 7 marbles in the beginning. So now, Steve has a total of 7 marbles + 3 marbles = 10 marbles after Sam gave him 3 marbles.. The answer is: 10.

At a flea market, Hillary sells handmade crafts for 12 dollars per craft. Today, Hillary sells 3 crafts and is given an extra 7 dollars from an appreciative customer. Later on, Hillary deposits 18 dollars from today's profits into her bank account. How many dollars is Hillary left with after making the deposit?
Let's think:
Hillary sells 3 crafts for 12 dollars each, for a total of 3 crafts * $12 / craft = $36. She receives an extra 7 dollars from a customer, increasing the total to $36 + $7 = $43. She then deposits 18 dollars in the bank, leaving her with $43 - $18 = $25.. The answer is: 25.