Mrs. Leifeste has a goal of walk/running 18 miles this month. She runs at a rate of 4 miles per hour. Which inequality can Mrs. Leifeste use to find h, the number of hours she should run in order to meet or exceed her goal?

After 6 new Olympic swimmers joined the USA swim team, they had 26 swimmers trying to win gold.  Which equation can be used to find n, the number of swimmers on the USA swim team before the six new Olympic swimmers joined. 

After Mr. Thomas added 8 fish to his fish tank, he had 12 fish total. Which equation can be used to find f, the number of fish Mr. Thomas had before he added the 8 fish to his fish tank?