Dean had 30 toy whistles. He gave 2 whistles to each of his 6 friends. How many whistles did Dean have left?

I have 45 cents in nickels. A nickel weighs 3 grams. What is the total weight of my nickels?

Evan and Brin are building a wall with blocks. Evan's wall was 3 blocks high and 6 blocks long. Brin's wall is 5 blocks high and 4 blocks long. How many more blocks did Brin use?

Red blocks weigh three times as heavy as blue blocks. There are 5 red blocks on one side of a seesaw. How many blue blocks are needed to balance the seesaw?

Alexa has 92 cents in her pocket. She wants to buy 3 pencils at the school supply store. Each penil costs 8 cents. How much money will Amy have left?