Matt spends 80 minutes washing the outside of his car and 1/4 that amount of time cleaning the inside. How long does he spend cleaning his car total? Think carefully first, then make a decision:
First find the time Matt spends cleaning the inside of his car: 80 minutes / 4 = 20 minutes. Then add that time to the time he spends cleaning the outside to find his total cleaning time: 20 minutes + 80 minutes = 100 minutes. So, the answer is 100.