Percents What is a percent Percents are ratios

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Percents

Percents

What is a percent? Percents are…. ratios that compare a number out of 100

What is a percent? Percents are…. ratios that compare a number out of 100 How to find a Percent: Percent ______ 100 = Part ______ Whole

Can you find the percent? 1. What percent of 92 is 66? (Round to

Can you find the percent? 1. What percent of 92 is 66? (Round to the nearest whole) Step 1: Set up a proportion x 66 ______ = 100 92 Step 2: Cross Multiply 92 x = 100(66)

Can you find the percent? Step 3: Solve for your variable 92 x =

Can you find the percent? Step 3: Solve for your variable 92 x = 100(66) x = 71. 739 72% 66 is 72% of 92!

More Examples… 2. Emma walks 2 miles to school. If Rachel’s walk is 80%

More Examples… 2. Emma walks 2 miles to school. If Rachel’s walk is 80% of the length of Emma’s walk, find the length of Rachel’s walk. 80 x _____ = 100 2 Rachel walked 1. 6 miles!

More Examples… 3. A jacket is on sale for 60% off its original price.

More Examples… 3. A jacket is on sale for 60% off its original price. The original price was $30. What is the sale price? 60 x _____ = 100 30 The sale price was $18!

More Examples… 4. Jon earns $36, 000 yearly. Of that he pays $12, 240

More Examples… 4. Jon earns $36, 000 yearly. Of that he pays $12, 240 for his mortgage. What percent of his earnings goes to the mortgage? x 12240 _____ = 100 36000 34% of his earnings goes to the mortgage!

Percent Increase & Decrease Percent Change: The ratio comparing the amount change to the

Percent Increase & Decrease Percent Change: The ratio comparing the amount change to the original amount. percent change = amount of change original amount Percent Increase: Describes how much the original amount increases. Percent Decrease: Describes how much the original amount decreases.

Examples… 1. According to the US Census, 72. 3 million children lived in the

Examples… 1. According to the US Census, 72. 3 million children lived in the United States in 2004. It is estimated that there will be 80. 3 million children in 2020. What is the percent increase, to the nearest percent? 80. 3 million - 72. 3 million = 8 percent change = 8 72. 3 Percent Change = 0. 1106 11%

More Examples… 2. Anthony buys a LCD monitor for his new computer. The price

More Examples… 2. Anthony buys a LCD monitor for his new computer. The price tag says the original price is $750 but it’s on sale for $487. 50. What is the percent decrease? $750. 00 - $487. 50 = $262. 50 percent change = 262. 50 750. 00 Percent Change = 0. 35 The LCD monitor was 35% off!

More Examples… 3. Ms. Breier bought a house for $125, 000. It has increased

More Examples… 3. Ms. Breier bought a house for $125, 000. It has increased in value by 7% in the past two years. Mr. Frommann bought a house for $135, 000. His house decreased in value by 4%. Who’s house is currently worth more? Ms. Breier: 7 x ___ = 100 125000 x = 8750 $125000 – $8750 = $116250 Mr. Frommann: 4 x ___ = 100 135000 x = 5400 $135000 - $54000 = $129600

More Examples… 4. You see a house for sale down the road from you.

More Examples… 4. You see a house for sale down the road from you. The house is listed for $294, 600. You are very interested and decide to put an offer down. You offer $287, 000 for the home. What is the percent decrease of the offer to the listing price? $294, 600 - $287, 000 = $7600 percent change = 7600 294600 Percent Change = 0. 0257 2. 6% Decrease!

Commission A fee paid to a person who makes a sale. ** Its is

Commission A fee paid to a person who makes a sale. ** Its is usually a percent of the selling price. Commission Rate: The percent of the sale. commission rate sales = commission

Examples… 1. Julie is paid a monthly salary of $2, 100 plus commissions. Last

Examples… 1. Julie is paid a monthly salary of $2, 100 plus commissions. Last month she sold one care for $39, 500, earning a 4% commission on the sale. How much was her commission? What was her total pay for the month? 0. 04 $39, 500 = commission Commission: $1, 580 Monthly Pay: $3, 680

Examples 2. A furniture sales associate earned $960 in commission in May. If his

Examples 2. A furniture sales associate earned $960 in commission in May. If his commission is 12% of his sales, how much were his sales in May? 0. 12 sales = $960 x = $81, 000 He had $81, 000 worth of sales in May.

Examples… 3. The realtor you hired in order to buy your home made $6,

Examples… 3. The realtor you hired in order to buy your home made $6, 796 in commission. You bought your home for $169, 900. What was the realtor’s commission rate? commission rate $169, 900 = $6, 796 x =. 04 The commission rate is 4%!

Sales Tax Sales tax is the tax on the sale of an item or

Sales Tax Sales tax is the tax on the sale of an item or service. ** Sales tax needs to be rounded to the nearest penny! Sales tax rate price = sales tax

Examples… 1. I bought a pair of jeans at the store. They were $39.

Examples… 1. I bought a pair of jeans at the store. They were $39. 99. I had to pay 8. 75% sales tax. How much did I have to pay in sales tax? 0. 0875 $39. 99 = sales tax Sales Tax: $3. 50 How much were the jeans with the sales tax? $39. 99 + $3. 50 = $43. 49 I spent $43. 49 total!

Examples… 2. If the sales tax rate is 7. 75%, how much sales tax

Examples… 2. If the sales tax rate is 7. 75%, how much sales tax would Michael have to pay in sales tax if he bought a portable DVD player for $59. 99 and two DVD’s for $17. 99 each? 0. 0775 ($59. 99+2($17. 99)) = sales tax Sales Tax: $7. 44 What is the total amount the Michael owes? $95. 97 + $7. 44 = $103. 41

Examples… 3. Explain whether adding 6% sales tax to a total gives you the

Examples… 3. Explain whether adding 6% sales tax to a total gives you the same result as finding 106% of the total. *Let’s use an example! -Say our total is $20. 50 0. 06 $20. 50 = sales tax Sales Tax: $1. 23 $20. 50 + $1. 23 = $21. 73 What is 106% of $20. 50? 1. 06 $20. 50 = sale price Sale Price: $21. 73 They’re the same!

Examples… 4. Explain how to find the price of an item if you know

Examples… 4. Explain how to find the price of an item if you know the total cost after 5% sales tax. Let x = the price of your item Let 0. 5 x = the sales tax x + 0. 5 x = total cost

Examples… 5. Explain whether the sales tax on a $20 item would be double

Examples… 5. Explain whether the sales tax on a $20 item would be double the sales tax on a $10 item. Justify your answer. *Lets use an example! -Say our sales tax is 8. 75%. 0. 0875 $20 = sales tax Sales Tax: $1. 75 0. 0875 $10 = sales tax Tax: $0. 88 (rounded) Sales $1. 75/2 = $0. 875

Examples… 6. You just bought your first home at a sale price for $249,

Examples… 6. You just bought your first home at a sale price for $249, 500. New York state sales tax is 8. 75%. How much did he pay in sales tax? 0. 0875 $249, 500 = sales tax Sales Tax: $21, 831. 25 How much did you pay for your home total? $249, 500 + $21, 831. 25 = $271, 331. 25

Simple Interest is money paid to the bank when you borrow the bank’s money

Simple Interest is money paid to the bank when you borrow the bank’s money OR it is money paid to you when you deposit money into a savings account. Simple Interest is a type of interest paid for the use of money. Simple Interest I=P Rate of interest is the percent charged or earned r Principal is the amount of money borrowed or invested t Time that the money is borrowed or invested (in years)

Examples… 1. Tristan borrowed $14, 500 from his brother and promised to pay him

Examples… 1. Tristan borrowed $14, 500 from his brother and promised to pay him back over 5 years at an annual simple interest rate of 7%. How much interest will he pay if he pays off the entire loan at the end of the fifth year? I = 14, 500 0. 07 5 I = $5, 075 What is the total amount he will repay? $14, 500 + $5, 075 = $19, 575

Examples… 2. Jamie invested $3, 500 in a mutual fund at a yearly rate

Examples… 2. Jamie invested $3, 500 in a mutual fund at a yearly rate of 6%. He earned $945 interest. For how long was the money invested. 945 = 3, 500 t 0. 06 4. 5 = t The money was invested for 4. 5 years!

Examples… 3. You are in the process of buying a home. You take out

Examples… 3. You are in the process of buying a home. You take out a mortgage loan for the sale price (including sales tax) of your house, which is $309, 938. Since you are a first time home owner and plan on living in the house for the next 20 years, you will get a mortgage rate of 4. 5%. How much interest will you pay on the entire loan? I = 309, 938 0. 045 20 I = 278, 944. 2 You will pay $278, 944 in interest!

#3 Continued… What will your monthly mortgage be, including interest? $309, 938 + $278,

#3 Continued… What will your monthly mortgage be, including interest? $309, 938 + $278, 944 = $588, 882 - There are 12 months in a year, so how many months are in 20 years? 20(12) = 240 months $588, 882 / 240 months Your monthly mortgage payment will be $2, 453. 68!