I go to the store to buy school supplies. I spend $8.52. I buy one notebook $2.55 and three pens which are each the same price. What is the price of a pen?

2 Answers
May 9, 2018

The price of the pen is $1.99

Explanation:

Notebook = x
Pen = y

Formula

Cost = x + 3y

if you know that the total cost is $8.52 and that the notebook cost $2.55, you can solve the question like so:

#$8.52 = $2.55 +3y#

#$8.52 - $2.55 = 3y#

#($5.97)/3 = y# --> cancels the 3

$1.99 = y

May 9, 2018

The price of one pen is #$1.99#.

Explanation:

Let's list out what we know:

One notebook #= $2.55#

3 pens #= # unknown price

Total spent #= $8.52#

Let's let the price of one pen be #p#. Now we form an equation to solve for #p#:
#2.55 + 3p = 8.52#

Subtract #color(blue)2.55# from both sides:
#2.55 + 3p quadcolor(blue)(-quad2.55) = 8.52 quadcolor(blue)(-quad2.55)#

#3p = 5.97#

Divide both sides by #color(blue)3#:
#(3p)/color(blue)3 = 5.97/color(blue)3#

#p = 1.99#

Therefore, the price of one pen is #$1.99#.

Hope this helps!