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### Course: Digital SAT Math>Unit 3

Lesson 3: Percentages: foundations

# Percents — Harder example

Watch Sal work through a harder Percents problem.

## Want to join the conversation?

• How do people think this explanation is easy? Am I dumb?
• Ok so the initial cost is \$40, and you get 30% off. This means you need to do 40(1-.3) because you want to find 30% off of 40, not 30% of 40. This gives you 40(.7) which is equal to 28. Now, to find the additional discount, you can do the final price divided by 28.
22.4/28 = 0.8
So now we know 22.4 (the final price) is 80% of the price with the discount (28). In other words, the second discount is 100-80 = 20%

I hope this made things clearer, though some might consider this problem easy, it's not easy for everyone - remember that at the end of the day everyone has their own strengths and weaknesses, and knowing these strengths and weaknesses will let you know what to work on and where to spend the most time on during the sat.
Lmk if you have any questions.
• bruh this is easier than the easy example
• yes it's
true
(1 vote)
• To find the additional discount, why not just do :

(28 - 22.40) / 28 = 0.2 = 20%

Seems faster than the calculation shown in the example.
• For sure!
• What type of cereal did he have?
• Asking the real questions!
• hahaha, This is very easy, easier than the basic example😅😅
• could you also use the difference/initial value method instead? I feel like it may be easier just to do the following:
5.6/22.40 x 100 which also gives you 20%
(I got the 5.6 by subtracting 22.4 from 28)
• agreed, it's easier at least for me
• Wait . . .
Let the additional discount be x so,
[(30+x)/100]*40=22.4
then x comes out to be 26 hence the additional discount should be 26%
In order to check my above answer
30% + 26% = 56%
and 56% of \$40 = \$22.4 i.e the final price. . .
IF I'M WRONG PLZ LET ME KNOW HOW ?
• There's one tiny detail that you may have overlooked. The additional discount is a percentage off of the sale price, not the actual price, as you have it in your equation. To do that, you would have to take the discounted price (.7 * 40) and apply the additional discount to that price: x * (.7*40). Set that equal to 22.4 and you would get a percent discount of .8, or 20% off.
(Forgot to mention this while writing the answer, but don't forget that the discounts are a percentage OFF, not just a percentage of the marked price. You'd then have to do 100 - the percent to find the discounted price (using 0.7 for 30% off instead of 0.3).
• This one was so confusing. Is there another way you can do the jeans problem?
• 30 percent of 40 dollars is 12 , subtract it with 40 and we get 28 dollars. Now to find out the additional discount you can choose one from the options as 12 and 20 are smaller number since we only need to get 22.4 so now discount off both and when you do 20% you will get 5.6 which if you subtract will give you 22.4
• can we use calculator for this kind of question on test day?