Word Problem - Linear Function

Question

I have just started doing linear functions in math class and while I understand them fairly well, I’m having trouble with how to extract the information I need to use in the question below.

A salesman is paid a weekly wage of £130. In addition he is paid a commission of 3% on the goods that he sells.

One week he sold goods to a value of £5000. Calculate his earnings that week.

Thankful for all the help I can get!

Answer 1

The first thing to do is to define the variables. In this case, there are two things you don't know that could vary. They are 1) the price of the goods that he sells, and 2) his total weekly earnings. So, let's let g = the price of the goods that he sells and let's let w = his total weekly earnings.

If he doesn't sell anything, he still gets £130 so you could say, w = £130. But as he starts to sell goods, he gets more and more weekly earnings. How do you know how much he gets? Well, the problem says he is paid a commission of 3% on the goods that he sells. So, since g is the price of the goods he sells, then his earnings on that would be 0.03*g (3% of it). That makes his weekly earnings equal to his base rate of £130 plus 0.03*g.

So w = 130 + 0.03*g

Answer 2

Commission earned is: 3% of 5000=(3/100)*5000=150

And weekly wage =130

So total earning for the week =150+130=280