# 6th Grade - Calculate Discounts And Tips

 Grade Level: 6th Skill: Fractions, Decimals and Percentages Topic: Calculate Discounts and Tips Goal: Calculate given percentages of quantities and solve problems involving discounts at sales, interest earned, and tips. Skill Description: Convert percents into decimals. Multiply converted decimals by dollar amounts to determine discount, interest, or tip. Use appropriate mathematical steps to calculate sales price and interest earned

## Building Blocks/Prerequisites

### Sample Problems

 (1) What is 25% of 40? (10) (2) Juan wants to purchase a DVD. The regular price of the DVD is \$25.89. This week all DVDs are 10% off. If Juan has \$24.00, does he have enough money to buy the DVD? (Yes, it will cost \$23.31) (3) Camtu and Stacy went out to lunch. Their bill totaled \$10.50. They would like to leave a 20% tip for their waitress. How much money should they leave? (\$2.10) (4) Rubi put \$250 in her savings account. She’ll receive 2% interest after one year. How much interest will she earn. (\$5.00) (5) If all bikes are on sale for 15% off, how much will a \$85.00 bike cost? (\$72.25)

### Learning Tips

 (1) Make this lesson high interest and valuable by stressing its importance in the everyday world. Collect real life proof of the importance of using this skill (i.e. ads that show discounts, bank statements that show interest, receipts with tip or discount). Emphasize how important this skill is and challenge your child to find the best deals or earn the most interest while “window shopping”. You may also want to take a fieldtrip to the clearance section your child’s favorite store and calculate discount and sale price for the items found there. (2) Discounts are always subtracted from the original price to find a sale price. However, it is very important to note that some problems simply ask for the discount, not the sale price. The discount is simply the amount that will be taken off of the original amount. To find a discount you always use one operation, multiply. To find sale price you must first multiply to find the discount and then subtract that amount from the original price. (3) Remind your child of short cuts like: 50% off is ½ off so, just divide by two; 25% off is ¼ off so divide by 4; 10% off can be calculated by moving the decimal from the dollar amount one space to the left and re-writing this as the discount amount. 20% can be found by finding 10% and doubling it (multiply by 2). (4) Review the steps to change a percent into a decimal. To change a percent into a decimal you need to find the decimal point (if there is no decimal point it is assumed to be behind the last number before the percent sign) and move the decimal two spaces to the left. For example, 100% = 1.00, 65% = .65, and 1.25% = .0125. (5) Review the steps to find the percent of a number. Students will need to be able to do this in order to find a discount amount, tip or interest. For example, to find out what 15% of \$60 is your student will need to change the percent into a decimal and then multiply the decimal by the dollar amount. So, .15 x 60 = \$9.00.

### Online Resources

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### Extra Help Problems

 (1) What is 60% of 500? (300) (2) Find 25% of 78. (19.5) (3) What is 95% of 32. (30.4) (4) Find 4% of 100. (4) (5) What is 35% of 183? (64.05) (6) All video games have been discounted 25%. What will the discount be on a game with the original price of \$56.25? (\$14.06) (7) Puppies are on sale for 60% off. Dulce found a \$65 puppy she’d like to buy. How much will she pay for the puppy? (\$26.00) (8) Steven found a watch he’d like to buy for his father. It’s regular price is \$99. It is on sale for 10% off. How much money will he save if he buys the watch while it’s on sale? (\$9.90) (9) All cds are ½ off this week. How much will Tony pay for a \$25.00 cd? (\$12.50) (10) If the regular price of a bike is \$135.00 and it is 40% off, what is the discount amount? (\$54.00) (11) Shayna and Marielle went to lunch. Their bill came to \$15.38. They’d like to leave their server a 20% tip. How much tip should they leave? (\$3.07) (12) Bill, Joey, and Tom went to lunch. Their bill came to \$26.25. If they leave an 18% tip, how much will they leave? (\$4.73) (13) Will, Darnel and Cecilia went to dinner. Their total bill came to 86.45. If they leave a 20% tip what is the total they spent on dinner? (\$103.74) (14) Daniella’s restaurant bill has items in the amount of \$2.00, \$3.25, and \$89.99. If Daniella wants to leave a 20% tip, what is the total amount she needs to pay? (\$114.29) (15) Maria and her family went out to dinner to celebrate her birthday. The bill came to \$125.50. What is the total her family paid if they left an 18% tip? (\$148.09) (16) Green Bank is offering 5% interest for savings accounts. If Jack puts \$430.00 into saving for one year, how much interest will he earn? (\$21.50) (17) Green Bank is offering 5% interest for savings accounts. If Jack puts \$430.00 into saving for three years, how much interest will he earn? (\$64.50) (18) Calculate the interest for one year. \$156.25 at 4% interest (\$6.25) (19) Calculate the interest for 2 years. \$242.30 at 5.6% interest (\$27.14) (20) Calculate the interest for 7 years. \$500,250 @ 4% (\$140,070.00) (21) Find the sale price. \$256.27 at 75% off (\$64.07) (22) Find the discount amount. \$2,677.00 at 65% off (\$1,740.05) (23) Find the discount. \$3,896.42 at 45% off (\$1,753.39) (24) Find the sale price. \$654.20 at 50% off (\$327.10) (25) Find the discount amount. \$28,479.00 at 30% off (\$8,543.70)