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I have to answer this problem and i have answered it but my dad and i keep arguing about whos right. Could someone tell me the answer.
The question is:
Elle wanted to buy a beach towel that was on sale for 20% off. She had $60 which was exactly enough. What was the price of the beach towel before it was put on sale?
What has happened is that you have taken away 20% (which is 20/100) from the original price (100%) leaving you with 80% (which is 80/100) which is of course $60.
So if we make X the original price
then $60 = X x (1-(20/100))
so $60 = X x 0.8
divide both sides by 0.8 and X = $60/0.8 = $75
So the original price was $75
Get a ruler in your hands. Measure things until you start to understand how a ruler works. Measure some stuff and figure out where the center is. Say you measure a book and it's 7/8" thick. You look at your ruler and see that every eighth is divided into two sixteenths, so obviously half of 7/8" is going to be 7/16". If you write that out you have 1/2 x 7/8 = 7/16. And you notice that 1/2 is divided into 2/4 and then into 4/8 and so on, so you can convert anything to anything by multiplying all the numbers on top and then all the numbers on bottom.
Other rulers are divided into 10 and 100 parts. But an inch is still an inch, so anything on one ruler can be translated to the other ruler. A half inch on one ruler is 5/10 or 50/100 on the other. An eighth inch is just 12.5 marks when you have 100 marks per inch. A metric ruler divides an inch into 25.4 parts, so a half inch would be 12.7 of those parts. Pretty simple, isn't it? Practice this a bit and people will think you went to wizard school.
Percent is simply a ruler with 100 marks. The only confusion is trying to keep track of what the marks represent. You are given that 80 marks are worth $60 so each mark is worth $60/80 = $0.75 and 100 marks are worth 100 x $0.75 = $75.
Thank you this makes a lot of sense :)
thank you so much i figured it out just before I came on so thank you !!!