Math Problem of the Week - Upper Elementary - July 25, 2021 to July 31, 2021

Upper Elementary: 

Question: Gasoline costs $1.45 per gallon. If a car's gas tank holds 15 gallons in total and is only ¹/₅ full right now, then how much will it cost to fill up the tank?

Answer: $17.40

Solution: If the gas tank is ¹/₅ full, then it will need ⁴/₅ × 15 = 12 gallons of gas to fill it. The 12 gallons of gas it takes to fill the tank costs $1.45 × 12 = $17.40.