3 3/7 (it can also be written as 24/7)
When dividing numbers by fractions it's the same as multiplying by the reciprocal so 4 divided by 7/6 is the same as 4 multiplied by 6/7 (which can also be written as 4/1 x 6/7 is that makes it easier to multiply) which equals 24/7 (or 3 3/7 which is the same thing just turned into a mixed number)