Answer:
4 five litres of gas can.
Explanation:
Given that,
The gas tank of a riding mower holds = 5 litres of gas
We have 20 litres of gas can
Number of 5 litres gas tank that can be fill from full 20 litres gas can
= 20 * 1/5
= 20/5
= 4
So, the number of 5 litres gas tank that can be fill from full 20 litres gas can
= 4 five litres of gas can.