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2014-08-16T14:07:33+03:00
4)23(3a+7b) = 17(5a+9b)

69a +161b= 85a +153b

69a-85a=153b -161b

-16a = -8b |: (-2)

2a=b

a/b= 1/2

5)0,45ha= 4500m²
57dam²=5700m²

4500+5700=10 200m²

6)3/2 * 8/9  * 4/3  -1=

= 4/3 *4/3 -1=

=16/9-1=

=(16-9)/9=  7/9
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