5 Minute Check Complete in your notes. 1. 16 is 20% of what number? 2. What percent is 18 of 40? 3. 25% of 88 is what number? 4. 18% of 45 is what number?
5 Minute Check Complete in your notes. 1. 16 is 20% of what number?
5 Minute Check Complete in your notes. 1. 16 is 20% of what number? 20 100 = 16 ? 1 5 = 16 ? 5 x 16 = 80 x 16
5 Minute Check Complete in your notes. 2. What percent is 18 of 40?
5 Minute Check ? 100 = 9 20 9 x 5 = 45% Complete in your notes. 2. What percent is 18 of 40? ? 100 = 18 40 ? 100 = 9 20 9 x 5 = 45% x 5
5 Minute Check Complete in your notes. 3. 25% of 88 is what number?
5 Minute Check 1 4 = ? 88 1 x 22 = 22 Complete in your notes. 3. 25% of 88 is what number? 25 100 = ? 88 1 4 = ? 88 1 x 22 = 22 x 22
5 Minute Check Complete in your notes. 4. 18% of 45 is what number?
5 Minute Check Complete in your notes. 4. 18% of 45 is what number? 18 100 = ? 45 9 50 = ? 45 9 x 45 = 405 ÷ 50 = 8.1 ?
Quiz Review Complete in your notes. Write the percent as a decimal. 1. 25% Write the percent as a fraction. 2. 7 1 2 % Write each decimal as a percent. 3. 0.47 Write the fraction as a percent. 4. 3 10
Quiz Review Complete in your notes. Write the percent as a decimal. 1. 25%
0.25.% = 0.25 Quiz Review Complete in your notes. Write the percent as a decimal. 1. 25% 0.25.% = 0.25
Quiz Review Complete in your notes. Write the percent as a fraction. 2. 7 1 2 %
Quiz Review Complete in your notes. Write the percent as a fraction. 2. 7 1 2 % 7 1 2 % = 7 1 2 100 x 2 2 = 15 200 ÷ 5 5 = 3 40
Quiz Review Complete in your notes. Write each decimal as a percent. 3. 0.47
0.47.% = 47% Quiz Review Complete in your notes. Write each decimal as a percent. 3. 0.47 0.47.% = 47%
Quiz Review Complete in your notes. Write the fraction as a percent. 4. 3 10
3 10 = ? 100 3 x 10 = 30% Quiz Review Complete in your notes. Write the fraction as a percent. 4. 3 10 3 10 = ? 100 3 x 10 = 30% x 10 Must have the percent sign.
Lesson 2.8.b Solve Percent Problems Friday, Nov 11 Lesson 2.8.b Solve Percent Problems
Solve Percent Problems Objective: To solve percent problems which involve finding the whole or part.
Solve Percent Problems A proportion is an equation that shows that two rates are equivalent.
Percent of a Number A percent proportion can be used to solve percent problems. percent fraction ? 𝟏𝟎𝟎 = ? ? number fraction
Understanding the Percent Proportion In a percent proportion, the first fraction represents the percent (and will always have 100 in the denominator) and the second fraction represents the number. percent fraction ? 𝟏𝟎𝟎 = ? ? number fraction
Solve Percent Problems Ben has made 15 bird houses. This is 30% of the bird houses he must make. How many total bird houses must he make? ? 𝟏𝟎𝟎 = ? ?
Solve Percent Problems Ben has made 15 bird houses. This is 30% of the bird houses he must make. How many total bird houses must he make? ? 𝟏𝟎𝟎 = ? ? Where do we place the 30%?
Solve Percent Problems Ben has made 15 bird houses. This is 30% of the bird houses he must make. How many total bird houses must he make? 𝟑𝟎 𝟏𝟎𝟎 = ? ? Where do we place the 15?
Solve Percent Problems Ben has made 15 bird houses. This is 30% of the bird houses he must make. How many total bird houses must he make? 𝟑𝟎 𝟏𝟎𝟎 = ? ? Where do we place the 15? Do we expect the answer to be smaller or larger than 15?
Solve Percent Problems Ben has made 15 bird houses. This is 30% of the bird houses he must make. How many total bird houses must he make? 𝟑𝟎 𝟏𝟎𝟎 = ? ? Where do we place the 15? In the percent fraction is the smaller or larger number on top?
Solve Percent Problems Ben has made 15 bird houses. This is 30% of the bird houses he must make. How many total bird houses must he make? 𝟑𝟎 𝟏𝟎𝟎 = 𝟏𝟓 ?
Solve Percent Problems Ben has made 15 bird houses. This is 30% of the bird houses he must make. How many total bird houses must he make? 50 bird houses 𝟑𝟎 𝟏𝟎𝟎 = 𝟏𝟓 𝟓𝟎 Write the answer next to the problem, circle it and do not forget the units. ÷ 2 ÷ 2
Solve Percent Problems Fred completed 10 math problems. This is 40% of the number of math problems he has to do. How many math problems must he do? ? 𝟏𝟎𝟎 = ? ?
Solve Percent Problems Fred completed 10 math problems. This is 40% of the number of math problems he has to do. How many math problems must he do? 25 problems 𝟒𝟎 𝟏𝟎𝟎 = 𝟏𝟎 𝟐𝟓 Write the answer next to the problem, circle it and do not forget the units. ÷ 4 ÷ 4
Solve Percent Problems A store is having a sale where movies are 15% off their original price. A movie costs $30.How much is the discount? ? 𝟏𝟎𝟎 = ? ?
Solve Percent Problems A store is having a sale where movies are 15% off their original price. A movie costs $30.How much is the discount? $4.50 discount 𝟏𝟓 𝟏𝟎𝟎 = ? 𝟑𝟎 𝟑 𝟐𝟎 = ? 𝟑𝟎 3 x 30 = 90 ÷ 20 = 4.5 Write the answer next to the problem, circle it and do not forget the units. x ?
Solve Percent Problems In the first 6 games of the season, Dan made a hit 8 out of 25 times. What is his hitting percentage? ? 𝟏𝟎𝟎 = ? ?
Solve Percent Problems In the first 6 games of the season, Dan made a hit 8 out of 25 times. What is his hitting percentage? 32% 𝟑𝟐 𝟏𝟎𝟎 = 𝟖 𝟐𝟓 x 4 x 4
Solve Percent Problems A store is having a sale where everything is 40% off their original price. You buy a shirt for $23 before taxes. What was the original price of the shirt? ? 𝟏𝟎𝟎 = ? ?
Solve Percent Problems A store is having a sale where everything is 40% off their original price. You buy a shirt for $23 before taxes. What was the original price of the shirt? $57.50 𝟒𝟎 𝟏𝟎𝟎 = 𝟐𝟑 ? 𝟐 𝟓 = 𝟐𝟑 ? 5 x 23 = 115 ÷ 2 = 57.5 Write the answer next to the problem, circle it and do not forget the units. x ?
Solve Percent Problems A recipe for soup uses 12% tomato juice. If a batch contains 1.5 cup of tomato juice, how large is the batch of soup? ? 𝟏𝟎𝟎 = ? ?
Solve Percent Problems A recipe for soup uses 12% tomato juice. If a batch contains 1.5 cup of tomato juice, how large is the batch of soup? 12.5 cups 𝟏𝟐 𝟏𝟎𝟎 = 𝟏.𝟓 ? 𝟑 𝟐𝟓 = 𝟏.𝟓 𝟏𝟐.𝟓 Write the answer next to the problem, circle it and do not forget the units. ÷ 2 ÷ 2
Solve Percent Problems Beth has made 12 cupcakes. This is 30% of the cupcakes she must make. How many cupcakes must she make? ? 𝟏𝟎𝟎 = ? ?
Solve Percent Problems Beth has made 12 cupcakes. This is 30% of the cupcakes she must make. How many cupcakes must she make? 40 cupcakes 𝟑𝟎 𝟏𝟎𝟎 = 𝟏𝟐 ? 𝟑 𝟏𝟎 = 𝟏𝟐 𝟒𝟎 Write the answer next to the problem, circle it and do not forget the units. x 4 x 4
Solve Percent Problems Sally’s soccer team won 68% of the games they played. If they played 25 games, how many games did they win? ? 𝟏𝟎𝟎 = ? ?
Solve Percent Problems Sally’s soccer team won 68% of the games they played. If they played 25 games, how many games did they win? 17 games 𝟔𝟖 𝟏𝟎𝟎 = 𝟏𝟕 𝟐𝟓 ÷ 4 Write the answer next to the problem, circle it and do not forget the units. ÷ 4
Solve Percent Problems Mudrik installed a device on his car that guaranteed to increase his gas mileage by 10%. The gas mileage increased 3 miles per gallon after installing the device. How many miles per gallon did he get before the device was installed?
Solve Percent Problems Mudrik installed a device on his car that guaranteed to increase his gas mileage by 10%. The gas mileage increased 3 miles per gallon after installing the device. How many miles per gallon did he get before the device was installed? 30 mpg 𝟏𝟎 𝟏𝟎𝟎 = 𝟑 ? 𝟏 𝟏𝟎 = 𝟑 𝟑𝟎 Write the answer next to the problem, circle it and do not forget the units. x 3 x 3
Solve Percent Problems Yolanda’s club requires that 60% of the members be present for any vote. If at least 30 members must be present to have a vote, how many members does the club currently have?
Solve Percent Problems Yolanda’s club requires that 60% of the members be present for any vote. If at least 30 members must be present to have a vote, how many members does the club currently have? 50 members 𝟔𝟎 𝟏𝟎𝟎 = 𝟑𝟎 𝟓𝟎 Write the answer next to the problem, circle it and do not forget the units. ÷ 2 ÷ 2
Solve Percent Problems Kai calculates he spends 15% of a school day in science class. If he spends 75 minutes in science class, how many minutes does Kai spend in school?
Solve Percent Problems Kai calculates he spends 15% of a school day in science class. If he spends 75 minutes in science class, how many minutes does Kai spend in school? 500 minutes 𝟏𝟓 𝟏𝟎𝟎 = 𝟕𝟓 𝟓𝟎𝟎 Write the answer next to the problem, circle it and do not forget the units. x 5 x 5
Solve Percent Problems If you have 3 cups of pineapple juice, how many total cups of punch can you make?
Solve Percent Problems If you have 3 cups of pineapple juice, how many total cups of punch can you make? 15 cups 𝟐𝟎 𝟏𝟎𝟎 = 𝟑 ? 𝟏 𝟓 = 𝟑 ? x 3 x 3
Solve Percent Problems How many cups of sorbet are used to make 8 cups of punch?
Solve Percent Problems How many cups of sorbet are used to make 8 cups of punch? 𝟏𝟓 𝟏𝟎𝟎 = ? 𝟖 𝟑 𝟐𝟎 = ? 𝟖 3 x 8 = 24 ÷ 20 = 1 1 5 cups
Solve Percent Problems Before 1982, pennies were 95% zinc and 5% copper. If 100 pennies minted in 1980 have a mass of 15 grams, what is the total mass of 100 pennies?
Solve Percent Problems Before 1982, pennies were 95% zinc and 5% copper. If 100 pennies minted in 1980 have a mass of 15 grams, what is the total mass of 100 pennies? 𝟓 𝟏𝟎𝟎 = 𝟏𝟓 ? 100 x 3 = 300 grams x 3
Solve Percent Problems A store is having a sale where winter clothes are 60% of the original price. A sweater is on sale for $30. What was the original price of the sweater?
Solve Percent Problems A store is having a sale where winter clothes are 60% of the original price. A sweater is on sale for $30. What was the original price of the sweater? 𝟔𝟎 𝟏𝟎𝟎 = 𝟑𝟎 ? 100 ÷ 2= $50 ÷ 2
Solve Percent Problems The first year of ownership, a new car can lose 20% of its value. If a car lost $4,200 of value in the first year, how much did the car originally cost?
Solve Percent Problems The first year of ownership, a new car can lose 20% of its value. If a car lost $4,200 of value in the first year, how much did the car originally cost? 𝟐𝟎 𝟏𝟎𝟎 = 𝟒𝟐𝟎𝟎 ? 𝟏 𝟓 = 𝟒𝟐𝟎𝟎 ? 5 x 4200 = $21,000 x 4200
Solve Percent Problems Using what you know about percents, explain why a commercial that says “80% of dentists use this toothpaste” might be misleading.
Solve Percent Problems Using what you know about percents, explain why a commercial that says “80% of dentists use this toothpaste” might be misleading. Since only the percent is known, it is not known how many actual dentists use this toothpaste. They could have only surveyed 5 dentists and 4 chose this toothpaste.
Solve Percent Problems At a zoo, an Asian elephant eats roughly 5% of its body weight each day. If an Asian elephant eats 300 pounds of food a day, how much does it weigh?
Solve Percent Problems At a zoo, an Asian elephant eats roughly 5% of its body weight each day. If an Asian elephant eats 300 pounds of food a day, how much does it weigh? 𝟓 𝟏𝟎𝟎 = 𝟑𝟎𝟎 𝒘𝒉𝒐𝒍𝒆 𝟏 𝟐𝟎 = 𝟑𝟎𝟎 𝒘𝒉𝒐𝒍𝒆 20 x 300 =6,000; It would weigh 6,000 pounds.
Solve Percent Problems Agenda Notes Skills Practice 2.8.b Due by the end of the period Show all work and circle all answers! Chapter 2 Test Tuesday, Nov 15 Due to a meeting, no help session Monday