Question

Afla numerele necunoscute:a)(100-b:3)×5=250.b)(c:9:3)×2=20

Answer 1

(100 - b : 3) × 5 = 250

100 - b : 3 = 250 : 5

100 - b : 3 = 50

b : 3 = 100 - 50

b : 3 = 50

b = 50 × 3

b = 150
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( c : 9 : 3) × 2 = 20

c : 9 : 3 = 20 : 2

c : 9 : 3 = 10

c : 9 = 10 × 3

c : 9 = 30

c = 30 × 9

c = 270
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Am folosit ptr ambele exercitii metoda mersului invers .
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