5 / 7 × 3 + 5 / 7 × 4-5 / 7 = (5 / 36 + 1 / 13) × 13 = 45 × 44 / 1 = 85 × 84 / 1=

5 / 7 × 3 + 5 / 7 × 4-5 / 7 = (5 / 36 + 1 / 13) × 13 = 45 × 44 / 1 = 85 × 84 / 1=

（1）
5 / 7 × 3 + 5 / 7 × 4-5 / 7
=5 / 7 × (3 + 4-1)
=5 / 7 × 6
=30 out of 7
（2）
(5 / 36 + 1 / 13) × 13
=5 / 36 × 13 + 1 / 13 × 13
=65 out of 36 + 1
=101 out of 36
（3）
45 × 1 / 44
=(44 + 1) × 1 / 44
=44 × 1 / 44 + 1 × 1 / 44
=1 + 1 / 44
=1 and 1 / 44
（4）
85 × 1 / 84
=(84 + 1) × 1 / 84
=84 × 1 / 84 + 1 × 1 / 84
=1 + 1 / 84
=1 and 1 in 84

How much is 84 out of 85 times 37? It's due tomorrow. It's easy to calculate!

3108 out of 80

How to simply calculate 13 / 84 × 85

84×13/85
=(85-1)×13/85
=85×13/85-1×13/85
=13-13/85
=12 and 72 / 85