PARKLAND PERCNET OF A NUMBER
USE MENTAL MATH TO FIND THE PERCENT OF A NUMBER
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CALCULATE THE PERCENT OF A NUMBER A survey showed ¼% of 800 students use inline skates to get to school. How many students skate to school?
30 ¾ % of 400 students surveyed said they own a cell phone How many students own a cell Phone?
You have $40.12 in a savings plan. At the end of 1 year you will have 120% of what you started with. How much money will you have at the end of 1Year.?
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Remember you can always use proportions or decimals
USING A PROPORTION Set up a proportion that uses the percent over 100. Cross multiply to write an equation. Solve the equation. To set up your proportion, think, “IS over OF equals PERCENT over 100.”
EXAMPLE – WHAT IS 20% OF 30? = part whole 30 x = 100x 30(20) = 100x = x6
USING A DECIMAL Change the percent to a decimal. Multiply that decimal by the number you are finding the percent of.
EXAMPLE – WHAT IS 18% OF 70? 18% = x 70 = 12.6
3. A. THERE IS A DISCOUNT OF 25% OFF ON A $60 PAIR OF SHOES. HOW MUCH ARE THE SHOES? $45 d. Why is forty-five dollars correct? $60 x $15.00 $ $45
4. A. A SHIRT COST $30 PLUS 7% TAX. WHAT IS THE TOTAL COST? $32.10 d. Why is thirty-two dollars and ten cents correct? $30 x.07 $2.10 $ $32.10
5. A. A $300 BIKE IS ON SALE. HOW MUCH IS THE COST? $225 d. Why is two hundred twenty-five dollars correct? $300 x $75.00 $ $225