Question

[hoaithu truong]

Answer 1

[Kiều Vũ Linh]

a) 53,2 : (X - 3,5) + 45,8 = 99

53,2 : (X - 3,5) = 99 - 45,8

53,2 : (X - 3,5) = 53,2

X - 3,5 = 53,2 : 53,2

X - 3,5 = 1

X = 1 + 3,5

X = 4,5

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b) 71 + 65 × 4 = (X + 140)/X + 260

(X + 140)/X + 260 = 331

(X + 140)/X = 331 - 260

(X + 140)/X = 71

X + 140 = 71 × X

71 × X - X = 140

70 × X = 140

X = 140 : 2

X = 70

Answer 2

[Kiều Vũ Linh]

1) (455 - x : 2 × 6) : 5 = 31

455 - x : 2 × 6 = 31 × 5

455 - x : 2 × 6 = 155

x : 2 × 6 = 455 - 155

x : 2 × 6 = 300

x : 2 = 300 : 6

x : 2 = 50

x = 50 × 2

x = 100

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2) (674 - 23 × 23) : x × 2 = 58

(674 - 529) : x × 2 = 58

145 : x × 2 = 58

145 : x = 58 : 2

145 : x = 29

x = 145 : 29

x = 5

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3) 235 - x × 5 + 365 = x × 35

(235 + 365) - x × 5 = x × 35

600 - x × 5 = x × 35

x × 35 + x × 5 = 600

x × 40 = 600

x = 600 : 40

x = 15

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4) 674 + x : 3 × 18 - x × 46 = 541

674 + x × 1/3 × 18 - x × 46 = 541

x × 46 - x × 6 = 674 - 541

x × 40 = 133

x = 133 : 40

x = 3,325

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5) (x × 24) : (x × 4) = 132 - (x × 7)

6 = 132 - (x × 7)

x × 7 = 132 - 6

x × 7 = 126

x = 126 : 7

x = 18