Explanation:
The total price of 3 pencils and 1 protractor at $3 was 4 times the total price of 1 pencil and 1 eraser at $0.60. What is the price of 1 pencil?
when pencil = p
3p + 3 = 4(p + 0.6)
expand right side:
3p + 3 = 4p + 2.4
subtract 3 from both sides:
3p + 3 - 3 = 4p + 2.4 - 3
3p = 4p -0.6
subtract 4p from both sides:
3p - 4p = 4p -0.6 - 4p
-p = -0.6
divide both sides by -1:
(-p)/-1 = (-0.6)/-1
p = 0.6
so each pencil costs $0.60