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Question 318695: A car is for sale
It's marked down 10%
Then it's marked down 20% off the first sale price
Then it's marked down 25% off the second sale price
selling price $3240. What is the original price
I've tried adding 25% to the 3240. and going that way but it's not right
example:100.-25%is 75. but 75 + 25% is 93.75
please tell me what I am missing Thank you
Found 2 solutions by stanbon, jim_thompson5910:
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website! A car is for sale
It's marked down 10%
Then it's marked down 20% off the first sale price
Then it's marked down 25% off the second sale price
selling price $3240. What is the original price
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Note: I am assuming the 1st sale price is x
and the 2nd sale price is 0.90x
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Let the original price be "x".
Equation:
x - 0.1x - 0.2x - 0.25*0.9x = 3240
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0.7x-0.225x = 3240
0.475x = 3240
x = $6821.05
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Cheers,
Stan H.
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Answer by jim_thompson5910(35256) (Show Source):
You can put this solution on YOUR website! Unfortunately, the first solution is incorrect as the answer does not check.
Let x = original price of the car
Since "It's marked down 10%", this means that the car goes from the original price of 'x' dollars to  dollars. So after the 10% discount, the car is now 0.9x dollars. Plug in some numbers to help you grasp this.
Now, apply the 20% discount to the new price of 0.9x (not the old price of 'x' dollars) to get  . So after the 2nd discount of 20% (added on top of the first discount of 10%), the price of the car is now 0.72x
Finally, let's apply the third discount. So after applying the discount of 25% to the second sale price, we get 
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So after applying all three discounts (in that exact order), the final price of the car is  dollars.
Because we know that the final price is actually $3,240, this means that  . Now just divide both sides by 0.54 to isolate x and get 
So the solution is  which means that the price of the car was originally $6,000.
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Check:
Original Price: $6000
After 10% discount, price is now: 6000-0.1*6000 = $5,400
After 20% discount, price is now: 5400-0.2*5400 = $4,320
After 25% discount, price is now: 4320-0.25*4320 = $3,240
So the final price is $3,240 and this confirms our answer.
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