To find 20% of a number, divide the number by 5. Alternatively, divide the number by 10 and double the result. The document provides examples of finding 20% of various numbers using these methods. It also shows the percent equivalents for fractions from 20% to 100% and examples of calculating percentages for word problems involving finding percentages of totals.

1. 20% is 1/5
To find 20% of a number divide by 5
(Tip/time-saver: or divide by 10 and double)
40% = 2/5, 60% = 3/5; 80% = 4/5; 100% = 5/5.

2. 0% 20% 40% 60% 80% 100% 120% 140% 160% 180% 200%

3. Find the percent
1. 10 makes out of 50 attempts: 10 1
20%
50 5
2. 32 yes votes on 40 ballots: 32 4
80%
40 5
3. 1,200 adults out of 2,000 members:
1200 12 3
60%
2000 20 5

4. If the number is easily divisible by 5:
To find 20% of a number divide by 5
Examples:
20% of 30 is 6
20% of 45 is 9

5. If the number is not easily divisible by 5:
Divide by 10 and double
Examples:
20% of 31 is 6.2
20% of 230 is 46

6. Recall the strategy:
To find A% of B
You can change the percent to a fraction,
Find B divided by the bottom, then
Multiply by the top.
Find 60% of 35
3 45
60% of 45 45 3 9 3 27
5 5

7. Examples:
1. If the total revenue is $500 and 40% is profit, how
much is profit? 2
40% of 500 500 $200
5
2. If to make 30 tons cement mixture we 60% sand, how
much sand do we need? 60% of 30 18 tons
3. This year’s sales are 120% of last year’s sales. If last
year we sold $4,500, what are sales this year?
6 4500
120% of 4500 = of 4500 6 900 6 $5, 400
5 5
4. If commission is 20% and the sale was $2,340, what is
the commission?
2340 234 $468

8. Closing Notes
 Remember 