155 expressed as a sum to the power of 2and cube number

Atypical mre contains 1,200 calories.if the average solider eats 3 mre per day and is deployed for 15 months how many calories will be consumed by a 44 member platoon of soldiers

Suppose your school costs for this term were $4900 and financial aid covered 3/4 of that amount. how much did financial aid cover? and how much do you still have to pay?

How is working backward similar to solving an equation?