Question

Ex 1 și 6 pag 42


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Answer 1

1. 2×21=7×6
42=42*formeaza proportii*
225×4=900×1
900=900*formeaza proportii*
3×420=18×7
1260=126*nu formeaza proportii*
1,2×5=1×3
6=3*nu formeaza proportii*
1,2×5=2×3
6=6*formeaza proportii*

6.x×27=9×6
27x=64
×=54:27
x=2
2×y=6×3
2y=18
y=18:2
y=9
0,5×z=6x3
0,5z=18
z=18:0,5
z=36
a×3=10×1,2
3a=12
a=12:3
a=4
2,1×4=7×b
8,4=7b
b=8,4:7
b=1,2
1,8×2,52=u×1,12
1,12u=4,536
u=4,356:1,12
u=4,05
(x+3)×2=5×6
x+3=30:2
x+3=15
x=15-3
x=12
27×7x=45×42
189×=1890
x=1890:189
x=10

Answer 2

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