Estimate Percents
47% is about 50%. So about how much is 47% of $500?
50% of $500 is the same as 5 times 50 which is $250.
What is 25% of 320?
25/100=x/320
25times320=100x
8000=100x
8000/100=x
x=80
If there are 40 bears at a zoo and 16 of them are black bears, what percent of bears are black bears?
16/40=x/100
Set your ratio equal to another ratio with a denominator of 100 to find x, which will be the percent of bears that are black bears.
Now you can either simplify or use cross multiply (butterfly trick).
Let's simplify 16/40=2/5
2/5=x/100
x = 40%
Estimate 31% of 102
30% of 100 is 30
78% of the money collected at a charity goes to Israel. If $7000 was collected, to the nearest cent, how much goes to Israel?
.78 x 7000 = $5460
If there are 200 students in a grade and 25 of those students think football is the best sport, what percent of students think football is the best sport?
You need to set a proportion to find x, where x is the percent of students who think football is the best
25/200=x/100
25times100=200x
2500=200x
2500/200=x
x=12.5%
Estimate
12% of 78
Round 12% to 10%
Round 78 to 80
10% of 80
approx 8
Kate has a coin collection. She keeps 3 of the coins in a box, which is only 2% of her collection. What is the total number of coins in her collection?
3/x=2/100
3times100=2x
300=2x
300/2=x
x=150 coins
What percent of 19 is 4.75?
The questions says WHAT PERCENT, so it wants the percent, this means 4.75 is your part (is 4.75), and 19 is your whole (of 19).
p/100=4.75/19
19p=475
25%
Or you can divide 4.75 by 19 get 0.25, then multiply by 100 and you get 100%.
82% of students in YSZ are right handed. If there are to 704 students in YSZ, about how many are right handed?
82% is about 80%
704 is about 700
80% of 700 is 560, so about 560 students are right handed.
Kate bought a pack of stickers, 25% of which are animal stickers. If 400 stickers are animal stickers, how many stickers are in the pack?
25/100=400/x
Cross multiply and you get 40000 = 25x. Divide both sides by 25 and you get 1600 stickers.
Divide 17.10 by 90 and you get .19, multiply by 100 and you get 19%.
Charlie sold 62% of water bottles at the concession stand at a soccer game. If there were a total of 50 bottles, approximately how many bottles did Charlie sell?
62% is about 60%, so 60% of 50 is 30, so he sold about 30 bottles.
Ben bought some school supplies from Staples. He bought notebooks for $6.99, highlighters for $6.62 and pencils. The sales tax was $1.54. If the sales tax rate is 8.8%, how much did the pencils cost?
$1.54 is 8.8% (sales tax) which is the tax on the entire shopping list.
We would first need to write a proportion to find the cost of the entire shopping list, then subtract that by the cost of the notebooks and highlighters to find the cost of the pencils.
1.54/w=8.8/100
$17.50 - 6.99 - 6.62 =
$3.89
675 people were on line for a concert. Only 486 people got into the concert. What percent of people did NOT get into the concert?
This means 189 people did not get in. What is this as a percent? Set up the proportion
189/675=x/100
28% did not attend the concert.
Natanel and Yosef go for lunch. If their food and beverages cost $42.60 and there is an 8.5% meals tax, how much is the bill? Write your answer to the nearest cent.
If it asks how much their bill costs total.
8.5% of 42.60 is 3.621 which is $3.62.
Add that to $42.60 and you get $46.22