Lance is 39 years old. Ted is 22 years old. Rosalinda is 45 years old. How old is Erik if the mean age of the four friends is 33.5? (I forgot how to solve these problems _)

Question

Lance is 39 years old. Ted is 22 years old. Rosalinda is 45 years old. How old is Erik if the mean age of the four friends is 33.5? (I forgot how to solve these problems >_>)

anonymous · Answer

mean age means average

anonymous · Answer

so that means lance's age + ted's age + rosalinda's age + erik's age all divided by 4 = 33.5

anonymous · Answer

do you have an idea how to get erik's age now?

anonymous · Answer

$$33.5 = \frac{ 39 + 22 + 45 + x }{ 4 }$$

goldphenoix · Answer

Oh yes. Now it looks familiar.
Add 39 + 22 + 45 to get 106
Now it should look like

33.5 = 106 + x / 4?

anonymous · Answer

right

anonymous · Answer

but 106 + x should be a quantity

goldphenoix · Answer

Then you do 33.5 * 4 to get 134.

Now it should look like: 134 = 106 + x ?

anonymous · Answer

:)

goldphenoix · Answer

I'm guessing smiley face means yes.
Now subtract 134 from 106 to get 28.
Equation should look like 28 = x

So that means that Erik age is 28, yes?

anonymous · Answer

yep you can even check your work by finding the mean

goldphenoix · Answer

39 + 22 + 45 + 28 = 134
134 / 4 = 33.5
Alright, 28 is the answer.
Thanks for your help, hobbs and xlegendx.
I'm gonna give the medal to xlegendx, since you already have a medal, hobbs. ;)

anonymous · Answer

all good as long as you learned <3