Max has 5 red cars 1/3 of the cars are red how many are left.

So 5 red cars

1/3 of all cars are red

therefor

5=1/3 of all cars

'of' means multply

5=1/3 times all cars

multiply both sides by 3

15=all cars

how many are left

basically how many are NOT red

15=all

red=5

all-red=others

15-5=others=10

10 cars are left