Question

Thirty pounds of a salt-water solution contains fifteen percent salt. How much water must be added to weaken the solution to ten percent salt?

Answer 1

15 lb to i belive it to i fyou use the furmoata

Answer 2

`Formula\ for\ percen\ concentration:\\ Cp=(ms)/(mr)*100\%\\\\ ms-mass \ of\ substance\\ mr- mass\ of \ solution\\\\ mr=30 pound\\ ms=x\\ 30 \ pounds\ of \ salt-water\ solution-----cp=15\%\\ 30 \ pounds\ of \ salt-water\ solution + x\ water --cp=10\%\\ 15\%=(ms)/(30)*100\% \\ (15)/(100)=(ms)/(30)\\ 100ms=15*30\ |:100\\ ms=4,5\ pound\\ 10\%=(ms)/(30+x)*100\%\\ (10)/(100)=(4,5)/(30+x)\\ 10(30+x)4,5*100\\ 300+10x=450\\ 10x=150\ |:10\\ x=15 pound\\`
`15\ pounds\ of\ water\ must\ be\ added.`