Name: ______Period: ____
Packet 25: Percents
A percent (%) is a ratio that compares a number to 100. For example, 25% = or .25
To change a percent into a decimal move the decimal point 2 spaces to the LEFT!
Percents are used for calculating sales tax, tips, commission, grades, percent error, and percents of increase and decrease.
or
1) 36 is 18% of what number? / 2) Find 7.25% of 350 / 3) 5 is what percent of 25?4) The table shows the number of points each student in Will’s study group earned on the most recent math test. There were 88 points possible on the test. (Round answers to the nearest tenth).
Name / Will / Penny / Cheng / Mia / Rob
Score / 72 / 68 / 81 / 87 / 75
Find Will’s percent correct on the test. / Find Cheng’s percent correct on the test. / What was the highest percentage earned on the test? What was the lowest?
Class Practice
1) Find 2.5% of 600. / 2) 125% of what number is 60? / 3) 30 is what percent of 12?4) In a magazine, 30 pages of the 80 pages are devoted to sports. What percent of the magazine is devoted to sports? / 5) Jim read 296 pages of a 400 page book. What percent of the book did he read? / 6) Of 1600 radios inspected, 112 were defective. What percent of the radios were defective?
7) The U.S. Food and Drug Administration require food manufacturers to label their products with a nutritional label. The nutritional label below shows a portion of the information from a package of macaroni and cheese.
a) The label states that a serving contains 3 grams of saturated fat, which is 15% of the daily value recommended for a 2000-Calorie diet. How many grams of saturated fat are recommended for a 2000-Calorie diet?
b) The 470 milligrams of sodium (salt) in the macaroni and cheese is 20% of the recommended daily value. What is the recommended daily value of sodium?
NUTRITION FACTS
Serving Size 1 cup (228 g)
Servings per container 2
Amount per serving
Calories 250 Calories from fat 110
% Daily Value
Total Fat 12g 18%
Saturated Fat 3g 15 %
Cholesterol 30 mg 10%
Sodium 470 mg 20%
Total Carbohydrate 31g 10%
Dietary Fiber 0 g 0%
Sugars 5 g
Protein 5 g
Vitamin A 4% Vitamin C 2%
Calcium 20% Iron 4%
Percent Homework
1) Find 50% of 108 / 2) 15 is 30% of what number? / 3) 52 is what percent of 65?4) A 1 hour radio program is divided into the categories shown in the table to the right:
Category / Number of Minutes
Music / 18
News / 15
Sports / 12
Commercials / 9
Call-ins / 6
Mixed Review
5) At a meeting, there were 30 Democrats and 20 Republicans. Write each ratio as a fraction in lowest terms.a) Democrats to Republicans
b) Republicans to all meeting participants
c) All meeting participants to Democrats / 6) Find the unit price for each bottle of hair conditioner. Which is the best buy?
a) 8 oz for $1.49
b) 12 oz for $2.29
c) 15 oz for $2.75 / 7) Solve for x:
a)
b)
1) Maria went out to dinner with her family. The check was $67.95. How much would they leave for a 15% tip? / 2) Ms. Barns earns a base salary of $42,000 plus a 1.5% commission on sales. Her total sales one year were $700,000. Find her total pay for the year.
3) How much would the tax be on a $198 stereo when the sales tax is 5.25%? / 4) The cost of Dan’s school supplies was $49.80. He had a coupon for 30% off the entire purchase. What was the final price?
Agatha ApeSnail Claws
Maple Leaf Soufflé
Rainwater Tea
Bill Cost: / Georgia Giraffe
Sautéed Bark Strips
Maple Leaf Soufflé
Bar-B-Q Moss Burger
Algae Phosphate
Bill Cost: / Paul Peacock
Inchworms
Beetles
Birdseed Tofu(1/2)
Mud Puddle Shake
Bill Cost: / Tabatha Turtle
3 orders of Beetles
Mud Puddle Shake
Bill Cost: / Stephen Spider
Beetles
Potato Bug Casserole
Pine Needle Salad
Rainwater Tea
Bill Cost:
1) Agatha Ape took Stephen Spider to brunch. What was their total bill with 5% tax and a 12% tip? (Calculate bothwithout tax). / 2) Paul Peacock is a generous tipper. He left a 22% tip. How much did he leave for a tip? / 3) Georgia and Tabatha each left a 15% tip. What was the difference in their tips?
1) Amy is shopping for a new CD player. She finds one she likes for $225. The sales tax is 7.5%. What will be the total cost of the CD player? / 2) A cell phone distributor earns a yearly salary of $28,000 plus a 17.5% commission on sales. Find the total earnings for a year when the sales are $38,000.
3) A computer normally costs $1575. This week the computer is on sale for 30% off. What is the sale price of this computer? If I have to add 8% sales tax, what is the final price of the computer? / 4) The 15% tip on Craig’s lunch bill came to $2.40. What was the amount of the bill before the tip?
5) 112% of 180 is what? / 6) 27 is what percent of 36?
To find percents of increase and decrease:
1) Find the ______of increase or decrease.
2) Set up a proportion:
1) Find the percent of increase or decrease to the nearest whole percent. Was it an increase or decrease?Original price: $280
New price: $400 / 2) Joshua’s normal body temperature is 98.5˚F. Due to a cold, his temperature went up 3˚ F. To the nearest percent, what was the percent of increase in his body temperature?
3) A house was originally listed for sale at $250,000. After 3 months, the seller dropped the price to $235,000. What was the percent of decrease in the price? / 4) A can of soup had 480 mg of sodium per serving. The sodium was reduced to 360 mg per serving so that the soup could be advertised as “low sodium.” What was the percent change in sodium content?
5) A CD was marked down from $15 to $12. Find the percent of decrease. / 6) If the cost of a No. 2 pencil has increased from 8 cents to 18 cents over the last 10 years, what was the percent of increase?
1) John bough a tent for $77.50 last year. Now it costs $94.55. / 2) Rosanna’s temperature was 103˚ yesterday. Today it is 99˚.
3) The doctor saw 12 cases of chicken pox in February. In April he saw 54 cases. / 4) John fell off his skateboard 24 times last week. This week he fell only seven times.
5) Linda bought a robot last year for $72.00. This year the robot costs $80.00. / 6) Last year the ninth graders ate a total of 170 pounds of popcorn at freshmen orientation. This year they ate 195 pounds.
1) A new school advertised a low student to teacher ratio. What is the ratio in lowest terms if there are 25 teachers and 300 students? / 2) A store had a sale on mp3 players. At 9 a.m., the store had 150 mp3 players in stock. By 10 a.m., 80% of the mp3 players had been sold. How many mp3 players were sold in one hour?
3) What percent of 40 is 16? / 4) What is the percent of change for the following: Original Price: $30
New Price: $74 / 5) What is the percent of change for the following: Original Price: $72
New Price: $48
6) Dianna mixed 1.5 grams of sodium chloride with 75 milliliters of water. How many grams of sodium chloride should she mix with 175 milliliters of water to maintain the same mixture ratio? / 7) The total number of cats and dogs at a veterinary hospital on a busy day was 56. The ratio of cats to dogs was 3:5. Determine the number of each type of animal at the hospital that day.
8) The cost of one gallon of gasoline in New YorkState is $3.52 on a certain day. The cost of one gallon of gasoline in New Jersey is $2.82 on the same day.
a)Find the percent decrease in one gallon of gasoline in New Jersey when you compare it with the New YorkState price.
b)Find the percent increase in one gallon of gasoline in New YorkState when you compare it with the New Jersey price.
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