# Math Help - two word percentage problems?

1. ## two word percentage problems?

1) Steve and Jodi bought their house for $85,000 and sold it for$103,000 a few years later. What was the percent increase in the value of their house?

2) You have a cup of coffee that is 12% cream and another cup which is 22% cream. How much would you have to take from each cup to make a cup of coffee that is 15% cream?

Thanks!

2. Hello,

The percent increase x (in %) of a price N, is defined as :

N*(1+x)=N', where N' is the new price. So you just have to solve this equation with N=85.000 and N'=103.000

For the second one, name the variables.
If x is the quantity taken from the 12% cream cup, and y the quantity from the other, you have to find x and y by comparing the quantity of cream :

x*12% + y*22% = (x+y)*15%

Is there an information missing ? There are many solutions !

3. To find percentage change, use:

(new price - original price)/(original price). Then, change that decimal answer to a percent. I get somewhere around 21%.

In the second problem, you want 15% cream coffee, and you have 12% and 22% to work with. Note that 15 is 3/10 of the way from 12 to 22. (The difference of 22 and 12 is 10, and 12 + 3 = 15.) This means your final mixture should be 3/10 22% coffee and 7/10 12% coffee. In terms of actual quantities, I agree with the previous poster - you need some additional information, namely how much coffee you want to end up with. If you want, say, 10 ounces, then you would use 3 ounces of 22% coffee and 7 ounces of 12% coffee.