First, let's make all the mixed fractions into improper fractions. To do that, we multiply the whole number by the denominator and add the numerator; this new number becomes the numerator while we keep the same denominator, thus:
3 2/7 = 3 * 7 + 2 / 7 = 21 + 2 / 7 = 23/7
1 6/7 = 1 * 7 + 6 / 7 = 7 + 6 / 7 = 13/7
Our new problem is
23/7 - (13/7 + 2/5)
The next step to be able to simplify this is to have common denominators. To do that here, we will multiply the first two fractions by 5/5 and the third fraction by 7/7, thereby making all three fractions have a denominator of 35:
5/5(23/7) - [5/5(13/7) + 7/7(2/5)]
115/35 - (65/35 + 14/35)
Finally, we can add the fractions in the parenthesis, and then subtract that number from 115/35:
115/35 - 79/35
36/35
Answer:
36/35