Just the numbers
If (4/10 = 12/y), what is y?
y=30
Find 75% of 20.
15
I spent 10€ on my groceries last week. This week, I get a 50% discount. How much will I spend?
5€
Problem: Find 80% of 50.
Stephanie multiplies 50 by 80 to get 4000.
Stephanie needs to convert the percentage to a fraction or decimal before multiplying to get 40.
Find 10% of 450.
45.
If (9/24 = x/6), what is x?
x = 9/4 = 2.25
The price of a company’s stock increases from $32 per share to $40 per share in a three-day period. By what percent did the stock’s price increase?
25%
Problem: Find x given (7/9 = x/108).
Kathy cross-multiplies to get 7(108)=x/9. She then multiplies both sides by 9 to get x = 7(9)(108)=6804.
When she cross-multiplies, Kathy should get 7(108)=9x. Then, dividing by 9 gives the correct answer of x = 7*12=84.
Find 52% of 800.
416
If (7/11 = x/33 = 14/y), what are x and y?
x = 21, y=22
I'm expanding the width of my vegetable garden by 30% and reducing the length by 10%. (Currently the length is 10 meters and the width is 5 meters). By what percentage will the area grow?
New width: 6.5 m
New length: 9 m
Old area: 50 m
New area: 58.5 m
Percentage change in the area: 17%
Liam is buying pasta at the grocery store. Brand A is having a 15% sale with a normal price of 1€ for 500 grams of pasta. Brand B is having a 40% sale with a normal price of 1,5€ for 500 grams of pasta.
After considering his options, Liam decides that Brand B is cheaper because their discount is bigger.
Even though Brand B's discount is bigger, the difference in original price means that Brand A is cheaper.
Brand A: 1€ * (1-0,15) = 1€ * 0,85 = 0,85€
Brand B: 1.5€ * (1-0,40) = 1.5 € * 0,60 = 0,90€