# Question #82ae2

##### 1 Answer

#### Explanation:

The trick here is to realize that a solution's **mass by mass percent concentration**, **of solution**.

When you add

#"40 g + 100 g = 140 g"#

Now, you know that this solution contains

#100 color(red)(cancel(color(black)("g solution"))) * "40 g sugar"/(140color(red)(cancel(color(black)("g solution")))) = "28.6 g sugar"#

This means that your solution has a mass by mass percent concentration of

#color(darkgreen)(ul(color(black)("% m/m = 30% sugar")))#

The answer must be rounded to one **significant figure**, the number of sig figs you have for your values.

So, you can say that dissolving **of solution**.