Yesterday grace drove 31 1/2 miles she used 1 1/4 gallons of gasoline. What is the unit rate for miles per​ gallon? im stuck can some one plz help me it would be a huge help

Aswimming pool has an input pump for filling the pool and an output pump for emptying the pool. the input pump can fill the pool in 3 hours, and the output pump can drain the pool in 5 hours. as you go to bed, the pool is full, but a neighbor’s kid turns on the output pump. at midnight, you awake to find the pool half empty. immediately, you turn on the input pump, but you are sleepy and forget to turn off the output pump. at what time will the pool become full?

Gretchen is setting up for a banquet. she has 300 chairs and needs to distribute them evenly among t tables. how many chairs should she put at each table? write your answer as an expression.

Write two subtraction equations that are equivalent to 5 + 12 = 17.