Bill bought 4 pens for $12. Which of the following equations shows the relationship between the cost of pens, c, and the number of pens, x, bought? What will the cost of 20 pens be?

Question 1 options:

A. c = 3x, $12

B. x = 3c, $60

C. c = 3x, $60

D. x = 3c, $12

Answer: So bill bought 4 pens for $12, this means that each pen costs the total amount of money divided the amount of pens, this is $12/4 = $3

Then if you bought x pens, the total cost c (x) is: c (x) = $3*x

Then, if x is equal to 20, we need to see c (20) = $3*20 = $60

So the correct answer is C) c = 3x, $60

The answer is going to be a