Question

ex 2 va rog dau corona ​

Answer 1

Salut! Te voi ajuta eu!

2. a) $\frac{4}{13}$ = $\frac{12}{39}$

b) 10% din 50 g = 5g

c) 5% din 200 = 10

Sper că te-am ajutat!

Answer 2

Răspuns:

4/13=12/a

4·a=12·13

4a=156=>a=156:4=>a=39

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100ml sol sare.................10g sare

50ml solutie...........................x

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x=50·10/100 =>x=5 g sare

sau

10/100·50=500/100=5 g sare

________________

100 ml tinctura...............5 g iod

200 ml tincura.................x

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x=200·5/100 =>x=10 g iod

sau

5/100·200=1000/100=10 g iod