Question

va rog frumos ajutatima .....dau coroana .....urgent !!!!! ​

Answer 1

1.

md = 14g, m.apa = 66g

stim ca ms = md+m.apa = 14+66 = 80g

stim ca c% = mdx100/ms

= 14x100/80 = 17,5%

2.

md = 30g, c% = 15%

din c% => ms = mdx100/c%

= 30x100/15 = 200 g sol.

3.

ms1 = 400g, c1% = 30%

ms2 = 350g, c2% = 15%

"sa creasca cu 5 unitati".... nu are ce cauta aici......!!!!!!!

din c% =>

md1 = ms1xc1%/100

= 400x30/100 = 120 g

md2 = ms2xc2%/100

= 350x15/100 = 52,5 g

=> md.final = md1+md2 = 120+52,5 = 172,5 g

=> ms.final = ms1+ms2 = 400+350 = 750 g

=> c%.final = md.finalx100/ms.final

= 172,5x100/750 = 23%