Answer:
To find the answer, we need to subtract the amount of bags Ben used from the amount he bought:
6 and 3/5 - 4 and 1/5
To subtract fractions, we need to have a common denominator. The smallest common denominator for 5 and 20 is 20, so we'll convert both fractions:
6 and 3/5 = 6 * 5/5 + 3/5 = 30/5 + 3/5 = 33/5
4 and 1/5 = 4 * 20/20 + 1/5 = 80/20 + 1/5 = 81/20
Now we can subtract:
33/5 - 81/20
We need to convert the mixed number to an improper fraction and find a common denominator:
33/5 - 81/20 = 132/20 - 81/20
Now we can subtract:
132/20 - 81/20 = 51/20
So Ben has 51/20 bags of rocks left. This can be simplified to 2 and 11/20 bags.