Question

How much of water should be added to 45g of salt to obtain 15% salt solution?​

Answer 1

Explanation:

45+15 = 60

45/60

ans = 0.75

Answer 2

$\large\underline{\sf{Solution-}}$

To make a 15 % salt solution with 45 gm of salt, let assume that the amount of water added be x gm.

So,

Given that,

~ Mass of solute = 45 gm

~ Mass of solution = 45 + x

~ Concentration = 15 %

We know,

$\boxed{ \bf{ \:Concentration\% = \frac{Mass \: of \: solute}{Mass \: of \: solution} \times 100\%}}$

So, on substituting the values, we get

$\rm :\longmapsto\:15 = \dfrac{45}{45 + x} \times 100$

$\rm :\longmapsto\:1= \dfrac{3}{45 + x} \times 100$

$\rm :\longmapsto\:1= \dfrac{300}{45 + x}$

$\rm :\longmapsto\:45 + x = 300$

$\rm :\longmapsto\: x = 300 - 45$

$\bf\implies \:x = 255$

Thus,

255 gm amount of water should be added to 45g of salt to obtain 15% salt solution.

Note :-

1 liters of water = 1000 gm