SOLUTION: A sign says that the price marked on all music equipment is 30%off the original price ,you buy an electric guitar for the sale price of $315 , what was the original price? How to

Algebra.Com
Question 1023777: A sign says that the price marked on all music equipment is 30%off the original price ,you buy an electric guitar for the sale price of $315 , what was the original price?
How to solve this or what formula should I use

Answer by Theo(13342)   (Show Source): You can put this solution on YOUR website!
the basic formulas involved are:

sale price = original price minus discount.
discount = original price * discount percent / 100.

let s represent the sale price.
let p represent the original price.
let d represent the discount.
let k represent the discount percent.

the above formulas become:

s = p - d
d = p * k/100

we know that s = 315.
we know that k = 30.

formulas become:

315 = p - d
d = p * 30/100

simplify these formulas to get:

315 = p - d
d = .3p

since d = .3p, then the first formula can be shown as:

315 = p - .3p, after we replace d with its equivalent value of .3p.

simplify to get 315 = .7p.

divide both sides of this equation by .7 to get:

315/.7 = p

solve for p to get p = 450.

the original price is 450.

30% of 450 = 135.

450 - 135 = 315, which is the sale price.

numbers look good.

solution is that the original price is 450.

it doesn't really matter what variable names you choose as long as you can keep track as to what variable name represents what.







RELATED QUESTIONS

A sign says that the price marked on all music equipment is 30% off the original price.... (answered by ewatrrr)
Walmart has a bike on sale for $150. The sign next to it says that the price is $25 off... (answered by Boreal,math_helper,Alan3354,MathTherapy)
a music player is on sale for 15% of the original price the sales price is $170 what is... (answered by Cromlix)
You buy a big-screen tv for $2,040, which is 15% off the original price. What was the... (answered by nerdybill)
You buy a big-screen TV for $2,040, which is 15% off the original price. What was the... (answered by rfer)
How do I solve .....A music player is on sale for 25% off the original price of $95.00 .... (answered by fcabanski)
Gordons sporting goods had sold all its windbreaker jackets except one. It was so ugly... (answered by ankor@dixie-net.com)
A sign above a sweater says "Take an additional 50% off." The price tag shows a price... (answered by rfer)
how do we figure this out...a music player is on sale for 15% off of the original price.... (answered by checkley79,solver91311)