1 / 4 + 5 ÷ 3 and 1 / 2 = = 1=

1 / 4 + 5 ÷ 3 and 1 / 2 = = 1=

3/2

(+ 1 / 5) + (- 2 / 3) - (+ 1 / 4) - (- 4 / 5)

1. Remove brackets
2. General division
3. Calculation

1 / 4 + 2 / 3 + 5 / 3

1/4+2/3+5/3

2 / 5 + 1 / 2-3 / 4 =?
I just learned mixed operation of fraction addition and subtraction. I don't know much about it. Who can teach me?

3/20
Process:
General score 8 / 20 + 10 / 20-15 / 20 = 3 / 20

1 + 1 + 1 / 2 + 1 + 2 + 1 / 3 + 1 + 2 + 3 + 1 / 4 + 1+2+3+4… +One in 100
Simple calculation

1 + (1 + 2) 1 + (1 + 2 + 3) 1 + (1 + 2 + 3 + 4) 1 + (1 + 2 + 3 +... 100) 1 = 1 + 2 / (1 + 2) * 2 + 2 / (1 + 3) * 3 +. 2 / (1 + 100) * 100 = 1 + 2 (1 / 2-1 / 3 + 1 / 3-1 / 4 +. + 1 / 100-1 / 101) = 1 + 2 (1 / 2-1 / 101) = 1 + 1-2 / 101 = 200 / 101

1 / 2 + 2 / 2 + 3 / 2 + 4 / 2 + 5 / 2 +. + 100 / 2 = how much?

1/2+2/2+3/2+…… +100/2
=1/2(1+2+3+…… 100)
=1/2*5050
=2525

Divide 100 people into four groups. The number of the first group is 113 times that of the second group, and the number of the first group is 114 times that of the third group. How many people are there in the fourth group

The number of the second team accounts for 1 / 113 = 34 of the number of the first team; the number of the third team accounts for 1 / 114 = 45 of the number of the first team; the total number of the three teams accounts for 1 + 34 + 45 = 5120 of the number of the first team; because the total number of the four teams is 100, the number of the first team can only be 20, otherwise the total number will exceed 100; so the number of the fourth team: 100-20 × 5120 = 49 (people); a: then there are 49 people in the fourth group ．

Given a (A-1) + (B-A & # 178;) = - 4, find (A & # 178; + B & # 178;) △ 2-ab

a(a-1）+（b-a²）=﹣4
a²-a+b-a²=-4
-a+b=-4
a-b=4
（a²+b²）÷2-ab
=(a²-2ab+b²)/2
=(a-b)²/2
=4²/2
=8

A. B represents two non-zero natural numbers. If a * b = 3 / A + B, 7 * (6 * 9) is obtained

A * b = 3 / 3 (a + b)
7*（6*9）
=7*[(6+9)/3]
=7*5
=(7+5)/3
=4

If 3 / 17 of the reciprocal of a is equal to 2 / 9 of the reciprocal of B, which is bigger (a B is a non-zero natural number) will help me~

3/17×1/a=2/9×1/b
3/17b=2/9a
b=17/3×2/9a
b=34/27a
So b > a