PERCENTAGES
Where can we see percentages? Vocabulary Statistics Discounts in Stores Clothing Tags Finance – Mortgages/ Interest Rates
What is a PERCENT?! LET’S BREAK IT DOWN!!!!! PERCENT ↙ ↘ One Out Of One Hundred
When talking about percentages, one whole is represented by 100% The parts that make up the whole will always add to be 100% For example: If your grade on a test was 86%, this means 86% of your answers were correct and 14% of your answers were incorrect 86% + 14% = 100%
When calculating percentages, we will encounter the word “of” which means “to multiply” in mathematics In other words, we will convert our percent into a decimal and multiply the two values to get our result Let’s Review
Changing Percentages to Decimals Percentages are represented using the ‘%’ symbol To change from a percent to a decimal, we simply divide the percent by 100, or move our decimal point two places to the left!
1) 40% = ________3) 25% = _________ 2) 6% = ________4) 123% = ________ 5) 0.72 = ________%7) 0.04 = ________% 6) 3.29 = ________%8) = _______%
graystripegraystripe: once in the 4th grade this guy got a 2% on his math quiz so everyone called him milk for the rest of the year
What is 25% of 200? Step 1: Convert the Decimal to a Percent Step 2: ‘Of’ means to multiply. Multiply the two values
What is 3% of 19? 1.Convert to a Decimal 2.Multiply 1.Convert to a Decimal 2.Multiply
What is 260% of 36? 1.Convert to a Decimal 2.Multiply 1.Convert to a Decimal 2.Multiply
What is 0.2% of 119? 1.Convert to a Decimal 2.Multiply 1.Convert to a Decimal 2.Multiply
REVIEW Converting Fractions to Percentages Step 1: Divide the Fraction Step 2: Multiply the Decimal by 100
Some common fractions as percentages
What is 4 out of 18? 1.Divide 2.Multiply by Divide 2.Multiply by 100
What is 11 out of 21? 1.Divide 2.Multiply by Divide 2.Multiply by 100
What is 35 out of 42? 1.Divide 2.Multiply by Divide 2.Multiply by 100
Word Problems with Percentages Aaron’s shoe store is having a sale!!!! 30% off any pair of winter boots. You fall in love with the first pair you see. The regular price is $ What will the discounted price of the boots be? How much will the boots cost including tax?
Word Problems with Percentages I just finished writing Mary’s math test. I know the test was out of 52, and she told me my grade was 78%. How many questions did I get right?
Moving to the next level!!! 36 is 15% of what number?
Moving to the next level!!! What percent of 235 is 73?
Moving to the next level!!! A zoo has 15 emperor penguins. This makes up 30% of the total penguins at the zoo. How many penguins does the zoo have altogether?
Moving to the next level!!! A grizzly bear’s heart rate drops to 10 beats/minute when it is hibernating. This is 20% of its normal heart rate. How many heartbeats per minute does a grizzly bear have when it is not hibernating?
YOUR TURN!!!!