(13 and 2 / 3) △ 5 + (5 and 1 / 3) △ 5 + (196 and 3 / 7) × 1 / 5 - (+ 76 and 3 / 7) △ (- 5)=

(13 and 2 / 3) △ 5 + (5 and 1 / 3) △ 5 + (196 and 3 / 7) × 1 / 5 - (+ 76 and 3 / 7) △ (- 5)=

(13 and 2 / 3) △ 5 + (5 and 1 / 3) △ 5 + (196 and 3 / 7) × 1 / 5 - (+ 76 and 3 / 7) △ (- 5)
=(13 and 2 / 3) △ 5 + (5 and 1 / 3) △ 5 + (196 and 3 / 7) △ 5 + (+ 76 and 3 / 7) △ 5
=(13 + 2 / 3 + 5 + 1 / 3 + 196 + 3 / 7 + 76 + 3 / 7) △ 5
=(13 + 2 / 3 + 5 + 1 / 3 + 196 + 3 / 7 + 76 + 3 / 7) △ 5
=292÷5
=58.4

(- 13 and 1 / 3) × 1 / 5 + (- 5 and 2 / 3) × 1 / 5 + (- 196 and 1 / 7) × 5 - (+ 76 and 1 / 7) × 5

(- 13 and 1 / 3) × 1 / 5 + (- 5 and 2 / 3) × 1 / 5 + (- 196 and 1 / 7) × 5 - (+ 76 and 1 / 7) × 5
=[(- 13 1 / 3-5 2 / 3) - (196 1 / 7-76 1 / 7)] × 1 / 5
=【-19-120】×1/5
=-139×1/5
=-27.8

Estimate the integral part of the sum of 1 + 2 / 1 + 3 / 1 + 4 molecule 1 + 5 molecule 1 + 6 molecule 1 + 7 molecule 1 + 8 molecule 1
Estimate the integer part of the sum of 1 + 2 / 1 + 3 / 1 + 4 molecule 1 + 5 molecule 1 + 6 molecule 1 + 7 molecule 1 + 8 molecule 1. A, B is a positive integer no more than 20. If a molecule B = 18 molecule 1, find the value represented by a, B

(1) 1 + 1 / 2 + 1 / 3 + 1 / 4 + 1 / 5 + 1 / 6 + 1 / 7 + 1 / 8 = 1 + (1 / 2 + 1 / 4 + 1 / 8) + (1 / 3 + 1 / 6) + (1 / 5 + 1 / 7) = 1 + 7 / 8 + 3 / 6 + 12 / 35 = 1 + 7 / 8 + 1 / 2 + 12 / 35 ∵ 1 / 2 < 7 / 8 < 1,0 < 12 / 35 < 1 / 2 ∵ 1 + 1 / 2 + 1 / 2 + 0 < 1 + 7 / 8 + 1 / 2 + 12 / 35 < 1 + 1 / 2 + 1 / 2 + 1 / 2, i.e. 2 < 1 + 7 / 8 + 3 / 6 + 12 / 35

Find fractions greater than 7 / 5, less than 10 / 7, and the molecule is 17
Please provide solutions,

If we multiply 5 / 7 and 10 / 7 by an X so that X5 / 7 is less than 17 and X10 / 7 is more than 17, we can get x, and 17 / X is the result