Question

Aflați numărul n știind că
(12+n)÷4 =16
4×(3-n)=8
6×(5+2n)=30
9×(11-n)=81
2×(20+10n)÷30=6
3×(9-2n)=9

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Answer 1

Răspuns:

a) 12+n=16×4

12+n=64

n=64-12

n=54

b) 3-n=8:4

3-n=2

n=3-2

n=1

c) 5+2n=30:6

5+2n=5

2n=5-5

2n=0

n=0

d) 11-n=81:9

11-n=9

n=11-9

n=2

e) 2×(20+10n)=6×30

2×(20+10n)=180

20+10n=180:2

20+10n=90

10n=90-20

10n=70

n=70:10

n=7

f) 9-2n=9:3

9-2n=3

2n=9-3

2n=6

n=6:2

n=3