Presentation on theme: "Applying Ratios, Rates, and Proportions : Percent Proportion, Sales Tax, Tip, Discount, and Simple Interest."— Presentation transcript:
Applying Ratios, Rates, and Proportions : Percent Proportion, Sales Tax, Tip, Discount, and Simple Interest
Percent Proportion part = % whole 100
Percent Proportion Problems Remember: part / whole = % / 100 Find 20% of 375. x / 375 = 20 / 100 x = is what percent of 45? 27 / 45 = x / 100 x=60 75 is 25% of what number? 75 / x = 25 / 100 x = 300
PRACTICE PERCENT PROPORTION Workbook page 82 Team Captain = person who has a birthday closest to today. Choose a team name.
SALES TAX, TIP, & DISCOUNT –K–Knowing how to calculate sales tax, tip, and discounts will help you determine how much money youre actually spending when you shop or eat out.
Sales Tax, Tip, and Discount DefinitionFinding Tax, Tip, or Discount Finding Total Price Sales Tax: increases the final price (100% + tax) Multiply the item times the rate as a decimal. If a store charges 5% sales tax, do 1.05 x subtotal. Tip: increases the final price (100% + tip) Multiply the item times the rate as a decimal. To figure a 20% tip, do 1.2 x subtotal. Discount: decreases the final price (100% - discount) Multiply the item times the rate as a decimal. If a jacket is 20% off, do 0.8 x original price.
MONEY MATTERS A $53 racquet at Sports Galore is on sale for 20% off the regular price. What is the amount of the discount? What is the sale price ?
PRACTICE SALES TAX, TIP, DISCOUNT Workbook page 86 Team Captain = person who has the longest hair. Choose a team name. Omit the middle column Omit the first column
SIMPLE INTEREST Simple interest is the amount paid for the use of money.
FORMULA I = P x R x T
INTEREST EQUALS PRINCIPAL - the amount of money invested or borrowed RATE - in the annual interest TIME - in years
SAVINGS ACCOUNT You can also use the formula to find the simple interest when you deposit money in a savings account
INVESTING Angie has $500 in a savings account that pays 5% simple interest. How much interest will she earn in 2 years? How much interest will she earn if she withdraws the money after 9 months?
HOME IMPROVEMENT If you borrow $5,000 at 11.5% for 3 years to make home repairs and improvements. How much will you have to pay back, including interest?
PRACTICE SIMPLE INTEREST Team Captain = person who has the largest hands. Choose a team name. Middle column first Workbook page 87
PERCENT OF CHANGE When shopping for roses the originally cost was $36 dollars before Valentines Day is now on sale for $18 dollars. What is the percent of decrease of the roses? Created By:Lynn Husen & Pat Layton Maury Middle Dandridge, TN