Question

afla numerele necunoscute .a)(a-80)×2-146=24 b)(100- b÷3)×5=490 c)(c÷9÷3)×4=20

Answer 1

a) (a-80)×2-146=24
(a-80)×2=24+146
(a-80)×2=170 /:2
a-80=85
a=85+80
a= 165
Verificare: (165-80)×2-146=85×2=146 (A)

b) (100-b:3)×5=490
(100-b:3)=490:5
100-b:3=98
b:3=100-98
b:3=2 / ×3
b=6
Verificare: (100-6:3)×5=(100-2)×5=98×5=490(A)

c) (c:9:3)×4=20
c:9:3=20:4
c:9:3=5/×3
c:9=15/×9
c= 135
Verificare:(135:9:3)×4=(15:3)×4=5×4=20(A)

Succes!