SAT Math Problem Solving Percentages

#shorts

Two ways to do proportions and percentages problems.

[AlejandroGD]

I did like this:

We are substracting 40% of the original price to get $18.00, so:

x-0.4x=18
0.6x=18
x=18/0.6
x=30

[isakzadeng]

Another way round. Target 18. Multiply both by 4 and you will notice the pattern.
Eg.
30x4=120
45x4=180
Edit: we already know that 1 and 2 cannot be the original price. Just find the next wrong one. Sometimes its easier to find out the wrong one than trying to find the correct one.

[draken]

Is there a formula for percentages like for geometry and other algebra lessons? I don’t want to memorise the way, I want to understand it. Can u help me?

[JoyJoke]

I multiplied 18 with 1.6 to try and get the answer. I got 28.8, why is my method wrong?

[MrPuzzleCodes]

I thought sat was sooo much harderrrr. We learn to do that in europe like in 5th grade

[baraah]

My problem that I don’t speak English, so I couldn’t understand what the equations said even if I know how to do those types of equations put I don’t know what they want 🙂

[hrshh]

In India a 1standard student can easily do this 🇮🇳🇮🇳😭

[eaglehaus]

18 / 6 = 3
1 part = 3
10 parts = 3 * 10 = 30 ans

[RG-]

I found the answer, if 18 = 60 %, 0.3 = 1% and 30 is 100%

[hagailevin]

You could see that even if 45 loses 50% it still more tyan 18

[LycanFerret]

This just makes me hate that my school teachers didn't even understand the math they taught. It's so simple, yet when you're taught it by being shown the answer on a board and getting told "copy it" instead of learning how and when to use different math equations, a simple set-up and answer becomes impossible to recreate.

Like there was no reason I had 95s in every class except math where I got 60s-70s throughout 5th to 12th grade. That is the prime example of shit teaching.

[Sgth]

Even better. Just divide the remaining percentage, which is 60%.

18 ÷ 6/10

18 × 10 /6

3 × 10

30

[paxundpeace]

Don't you ever tell me that we learn nothing at school.

[andrewk-majordochomerepair]

Also by logic, not only can the original price not be less than the original price, if its only 40% off, the original price cannot be greater than less than 2x the sale price; i.e. even $36 would be too large a price for the original, so 40- something doesn't even make sense. In reality, one doesn't even need to calculate the original price of 30$, the other 3 answers logically don't make sense mathematically. Real numbers, data, not fake facts, 😆

[yourlocaldevil]

couldn’t you just do .6 times x = 18 (x would equal the original price) and solve it as an algebraic expression? x would equal 10.8 which is the original price. feel free to correct me if i’m wrong

[pinkaddiction]

I watched this 8 times and still don't understand where the hell 60% came from. ugh

[steelfalconx]

Yeah this isn't an sat question is a remedial junior high math question.