Răspuns:
Explicație pas cu pas:
a)
2×2×2×a=8
8×a = 8
a = 8 : 8
a = 1
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b)
8 : 4 × b = 10
2 × b = 10
b = 10 : 2
b = 5
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c)
c : ( 671 - 111×3×2) = 70
c : ( 671 - 333×2) = 70
c : ( 671 - 666 ) = 70
c : 5 = 70
c = 70 × 5
c = 350
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d)
1 000 - d × 2 - 25 × 4 = 800
1 000 - d × 2 - 100 = 800
1 000 - d × 2 = 800 + 100
1 000 - d × 2 = 900
d × 2 = 1 000 - 900
d × 2 = 100
d = 100 : 2
d = 50
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e)
e - 40 : 2 + 29 × 4 = 132
e - 20 + 116 = 132
e - 20 = 132 - 116
e - 20 = 16
e = 16 + 20
e = 36
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f)
f : 7 + 25 = 900 - ( 300 - 48 × 5 ) × 9
f : 7 + 25 = 900 - ( 300 - 240 ) × 9
f : 7 + 25 = 900 - 60 × 9
f : 7 + 25 = 900 - 540
f : 7 + 25 = 360
f : 7 = 360 - 25
f : 7 = 335
f = 335 × 7
f = 2 345
