1. Warm-Up
A farmer has determined that he has enough hay for 4 cows for 3 weeks. If the farmer suddenly obtains 2 more cows, how long can he expect the hay to last?
Hint: “How much” does one cow eat in 3 weeks?

2. Agenda Exploration 6.5 One more slide on Proportions Percents
Percent Problems
Homework

3. Let’s look again at proportions
Explain how you know which of the following rates are (equivalent) proportional?
6/10 mph
1/0.6 mph
2.1/3.5 mph
31.5/52.5 mph
240/400 mph
18.42/30.7 mph
60/100 mph

4. Percent Percent means per hundred.
50% means 50 per hundred, or 50/100.
95% means 95 per hundred, or 95/100.
2% means 2 per hundred, or 2/100.
315% means 315 per hundred, or 315/100.

5. Easy Percents--just know these
1 = 100%
1/3 = 33.3%, 2/3 = 66.6%
1/4 = 25%, 1/2 = 50%, 3/4 = 75%
1/5 = 20%, 2/5 = 40%, 3/5 = 60%, 4/5 = 80%
1/8 = 12.5%, 3/8 = 37.5%, 5/8 = 62.5%, 7/8 = 87.5%
1/10 = 10%, 2/10 = 20%, etc..

6. Fractions, Decimals, Percents
To write fractions as decimals or percents:
a/b means a ÷ b. Divide, and write the answer to get the decimal. Then, multiply by 100 to get the percent.
Example: 48/60 = 48 ÷ 60 = 0.8 = 80%
You try: 4/9, /20

7. Fractions, Decimals, Percents
To write decimals as fractions or percents:
Read the decimal without the word “point.” Simplify if necessary.
To write a percent, multiply by 100.
Example: = 9/100 = 9%
You try: , 0.59

8. Fractions, Decimals, Percents
To write a percent as a decimal, divide by 100.
To write a decimal as a fraction, read the decimal without the word “point.” Simplify if necessary.
Example: 591% = 5.91 = 5 91/100
You try: 3%, 62%, %

9. What happens if… What if you have 3 2/5%
Rewrite 2/5 as So 3 2/5% = 3.4%

10. Exploration 6.5 Sales #1 - 4 Decrease and Increase #5 - 6
General formula?