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PLEASE HELP

kareem cannot decide which of two washing machines to buy. The selling price of each is ​$390. The first is marked down by ​40%. The second is marked down by 10​% with an additional ​30% off. Find the sale price of each washing machine. Use pencil and paper. Explain why should buy the first washing machine rather than the second if the machines are the same except for the selling price.

User Benito
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1 Answer

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28 votes

Answer:

Explanation:

The first thing you have to do is find the price of each washing machine after they have been marked down.

The first washing machine is marked down by 40%. Because the price is going down by 40%, the new price will be 60% of the original $390. This is because 100 - 40 = 60. Get rid of 40% of something, and 60% is left.

Knowing this, we can mutiply $390 by 60%, which can also be written as the decimal 0.60.

390 times 0.60 = 234

Ok, so we have the price of the first washing machine. Now, lets look at the second.

Well, this is pretty simple. We do the same thing that we did with the first.

It's initially marked down by 10%, so we start with that. Since the entire price will be 10% less, and 100 - 10 = 90, we can mutiply $390 by 90%, which can be written as 0.90

390 times 0.90 = 351

Now, the new price, $351, is marked down by 30%.

100 - 30 = 70, so we mutiply 351 by 70%, or 0.70.

351 times 0.70 = 245.7

So, now we have the two prices. Washing machine number one is $234, and washing machine number two is $245.70. But why?

Well, it's because of the different ways the two washing machines go on sale. The first one goes on sale all at once, so the ENTIRE price of $390 dollars goes down by 40%.

However, with the second washing machine, the way it goes on sale changes the amount of money that is saved.

Since the second washing machine goes on sale twice, the second sale is a sale on the new price resulting from the first sale.

Since the second sale is 30% off of $351, it is less of a sale than if it was 40% off of $390

This is because, the smaller a number is, the smaller the percentage you are taking away from it is.

For example, if you take away 50% from 1000, you get 500. But, if you take away 40% from 1000 to get 600, and then 10% away afterwards, 10% from 600 is less than 10% from 1000.

Hope that wasn't too confusing, It's not easy to explain using a keyboard.

User Ygee
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