Tax, Tip, Discount, I=prt, Percent Of Change

1. Maggie's father bought a lawn mower. He borrowed $700.00 at a 15% interest rate for 3 years. How much interest will he pay? (Use the formula I=prt)

$32.00

$315.00

$383.00

$655.00

The formula I=prt is used to calculate the interest, where I represents the interest, p represents the principal amount (in this case, $700.00), r represents the interest rate (15% or 0.15), and t represents the time period (3 years). Plugging in the values into the formula, we get I = 700 * 0.15 * 3 = $315.00. Therefore, the correct answer is $315.00.

Explanation

The formula I=prt is used to calculate the interest, where I represents the interest, p represents the principal amount (in this case, $700.00), r represents the interest rate (15% or 0.15), and t represents the time period (3 years). Plugging in the values into the formula, we get I = 700 * 0.15 * 3 = $315.00. Therefore, the correct answer is $315.00.

2. The cost of a lamp is $29.95. Sales tax is 6%. About how much will the lamp cost, including tax?

$29.00

$30.00

$32.00

$33.00

The cost of the lamp is $29.95. To find the cost including tax, we need to add the sales tax of 6% to the cost of the lamp. 6% of $29.95 is $1.80. Adding this to the cost of the lamp gives us a total cost of $31.75. Since the options given are rounded to the nearest dollar, the closest option is $32.00.

Explanation

The cost of the lamp is $29.95. To find the cost including tax, we need to add the sales tax of 6% to the cost of the lamp. 6% of $29.95 is $1.80. Adding this to the cost of the lamp gives us a total cost of $31.75. Since the options given are rounded to the nearest dollar, the closest option is $32.00.

3. Last year, Maria earned $5.00 per hour baby-sitting. This year she earns $5.50 per hour. What is the percent of change?

10% decrease

10% increase

9% increase

9% decrease

The percent of change can be calculated by finding the difference between the new and old values, dividing it by the old value, and then multiplying by 100. In this case, the difference between $5.50 and $5.00 is $0.50. Dividing $0.50 by $5.00 gives 0.10, which when multiplied by 100 gives 10%. Therefore, the percent of change is a 10% increase.

Explanation

The percent of change can be calculated by finding the difference between the new and old values, dividing it by the old value, and then multiplying by 100. In this case, the difference between $5.50 and $5.00 is $0.50. Dividing $0.50 by $5.00 gives 0.10, which when multiplied by 100 gives 10%. Therefore, the percent of change is a 10% increase.

4. One month, the price of gas was $3.59. The next month the price of gas was $3.74. What was the approximate percent of change from one month to the next?

4% increase

4% decrease

3 % increase

3% decrease

The approximate percent of change from one month to the next can be calculated by finding the difference between the two prices and dividing it by the original price. In this case, the difference is $3.74 - $3.59 = $0.15. Dividing this by $3.59 gives us approximately 0.0418. Multiplying this by 100 gives us approximately 4.18%. Rounding this to the nearest whole number, we get 4%. Therefore, the correct answer is 4% increase.

Explanation

The approximate percent of change from one month to the next can be calculated by finding the difference between the two prices and dividing it by the original price. In this case, the difference is $3.74 - $3.59 = $0.15. Dividing this by $3.59 gives us approximately 0.0418. Multiplying this by 100 gives us approximately 4.18%. Rounding this to the nearest whole number, we get 4%. Therefore, the correct answer is 4% increase.

5. Sam's bill at the restaurant came to $28.15. He wants to leave a 15% tip. What is the total cost?

$23.93

$32.37

$28.15

$4.22

To calculate the total cost, we need to add the bill amount to the tip. The tip is calculated by multiplying the bill amount by the tip percentage (15%). Therefore, the tip amount is 28.15 * 0.15 = $4.22. Adding this to the bill amount gives us a total cost of $28.15 + $4.22 = $32.37.

Explanation

To calculate the total cost, we need to add the bill amount to the tip. The tip is calculated by multiplying the bill amount by the tip percentage (15%). Therefore, the tip amount is 28.15 * 0.15 = $4.22. Adding this to the bill amount gives us a total cost of $28.15 + $4.22 = $32.37.

6. Mrs. York's homeroom recorded the total number of books read per month. In May, they read 72 books, and in June they read 56 books. What was the approximate percent decrease from May to June?

4% decrease

4.5% decrease

16% decrease

22% decrease

The approximate percent decrease from May to June can be calculated by finding the difference between the two numbers (72 - 56 = 16) and then dividing that difference by the initial number (16 / 72 = 0.2222). Multiplying this decimal by 100 gives us the approximate percent decrease, which is 22%.

Explanation

The approximate percent decrease from May to June can be calculated by finding the difference between the two numbers (72 - 56 = 16) and then dividing that difference by the initial number (16 / 72 = 0.2222). Multiplying this decimal by 100 gives us the approximate percent decrease, which is 22%.

7. A half-cup of brownie mix has 5% of the total daily allowance for cholesterol. The total daily allowance of cholesterol is 300 mg. How much cholesterol does a half-cup of brownie mix have?

15 mg

20 mg

60 mg

100 mg

A half-cup of brownie mix has 5% of the total daily allowance for cholesterol, which is 300 mg. To find out how much cholesterol a half-cup of brownie mix has, we need to calculate 5% of 300 mg. 5% of 300 mg is equal to 0.05 * 300 mg, which comes out to be 15 mg. Therefore, a half-cup of brownie mix has 15 mg of cholesterol.

Explanation

A half-cup of brownie mix has 5% of the total daily allowance for cholesterol, which is 300 mg. To find out how much cholesterol a half-cup of brownie mix has, we need to calculate 5% of 300 mg. 5% of 300 mg is equal to 0.05 * 300 mg, which comes out to be 15 mg. Therefore, a half-cup of brownie mix has 15 mg of cholesterol.

8. Joe's science average in the first quarter was an 83. In the second quarter, his average was 93. What was the percent increase in his math grade?

6% increase

8.3% increase

11% increase

12% increase

To find the percent increase in Joe's math grade, we need to calculate the difference between his second quarter average (93) and his first quarter average (83). The difference is 10. Then, we divide this difference by his first quarter average (83) and multiply by 100 to get the percentage increase. (10/83) * 100 = 12.04%. Rounded to the nearest whole number, the percent increase is 12%.

Explanation

To find the percent increase in Joe's math grade, we need to calculate the difference between his second quarter average (93) and his first quarter average (83). The difference is 10. Then, we divide this difference by his first quarter average (83) and multiply by 100 to get the percentage increase. (10/83) * 100 = 12.04%. Rounded to the nearest whole number, the percent increase is 12%.

9. The price of a dvd is marked down from $12.50 to $10.00. What is the percent of decrease?

20%

25%

40%

80%

The percent of decrease can be calculated by finding the difference between the original price and the new price, dividing it by the original price, and then multiplying by 100. In this case, the difference is $2.50 ($12.50 - $10.00). Dividing $2.50 by $12.50 gives 0.2, and multiplying by 100 gives 20%. Therefore, the percent of decrease is 20%.

Explanation

The percent of decrease can be calculated by finding the difference between the original price and the new price, dividing it by the original price, and then multiplying by 100. In this case, the difference is $2.50 ($12.50 - $10.00). Dividing $2.50 by $12.50 gives 0.2, and multiplying by 100 gives 20%. Therefore, the percent of decrease is 20%.

10. Josh bought a game that sold for $64. It was discounted 10%. The sales tax was 6%. What was the final cost?

$54.14

$57.60

$61.06

$66.18

After applying a 10% discount to the original price of $64, the price of the game becomes $57.60. Then, a 6% sales tax is applied to the discounted price, resulting in an additional cost of $3.46. Adding this tax to the discounted price gives a final cost of $61.06.

Explanation

After applying a 10% discount to the original price of $64, the price of the game becomes $57.60. Then, a 6% sales tax is applied to the discounted price, resulting in an additional cost of $3.46. Adding this tax to the discounted price gives a final cost of $61.06.

11. Mitch bought a shirt regularly priced $35.00. With a 30% markdown and a sales tax of 6%, about what is the cost of Mitch's shirt?

$37

$26

$23

$22

The regular price of the shirt is $35.00. With a 30% markdown, the price is reduced by 30% of $35.00, which is $10.50. Therefore, the discounted price of the shirt is $35.00 - $10.50 = $24.50. Adding a 6% sales tax to this price, we get 6% of $24.50, which is $1.47. Therefore, the total cost of Mitch's shirt is $24.50 + $1.47 = $25.97. Rounded to the nearest dollar, the cost of Mitch's shirt is $26.

Explanation

The regular price of the shirt is $35.00. With a 30% markdown, the price is reduced by 30% of $35.00, which is $10.50. Therefore, the discounted price of the shirt is $35.00 - $10.50 = $24.50. Adding a 6% sales tax to this price, we get 6% of $24.50, which is $1.47. Therefore, the total cost of Mitch's shirt is $24.50 + $1.47 = $25.97. Rounded to the nearest dollar, the cost of Mitch's shirt is $26.

12. If the price of ice cream is raised from 50 cents to 60 cents, what is the percent increase in the price?

10%

16.7%

20%

83.3%

When the price of ice cream is raised from 50 cents to 60 cents, the increase in price is 10 cents. To find the percent increase, we divide the increase by the original price (10/50) and then multiply by 100. This gives us a percent increase of 20%.

Explanation

When the price of ice cream is raised from 50 cents to 60 cents, the increase in price is 10 cents. To find the percent increase, we divide the increase by the original price (10/50) and then multiply by 100. This gives us a percent increase of 20%.

13. 3,975 people were asked to participate in a survey. Only 26% of the people answered the survey questions. About how many people answered the survey?

1,800

1,500

1,000

900

Out of the 3,975 people who were asked to participate in the survey, only 26% actually answered the survey questions. To find out how many people answered the survey, we can calculate 26% of 3,975. By multiplying 3,975 by 0.26, we get 1,033.5. Since we cannot have half a person, the closest whole number to 1,033.5 is 1,000. Therefore, approximately 1,000 people answered the survey.

Explanation

Out of the 3,975 people who were asked to participate in the survey, only 26% actually answered the survey questions. To find out how many people answered the survey, we can calculate 26% of 3,975. By multiplying 3,975 by 0.26, we get 1,033.5. Since we cannot have half a person, the closest whole number to 1,033.5 is 1,000. Therefore, approximately 1,000 people answered the survey.

14. Mark had a salary of $36,500 last year. This year his salary is $38,325. what percent raise did Mark receive?

3%

4%

5%

6%

To find the percentage raise, we need to calculate the difference between Mark's salary this year and last year, which is $38,325 - $36,500 = $1,825. Then, we divide this difference by Mark's salary last year and multiply by 100 to get the percentage raise. Therefore, the percentage raise Mark received is (1825/36500) * 100 = 5%.

Explanation

To find the percentage raise, we need to calculate the difference between Mark's salary this year and last year, which is $38,325 - $36,500 = $1,825. Then, we divide this difference by Mark's salary last year and multiply by 100 to get the percentage raise. Therefore, the percentage raise Mark received is (1825/36500) * 100 = 5%.

15. Mrs. Pearson borrowed $1,000.00 for a year at a rate of 6% per year. What was the total amount she needed to pay off the loan at the end of the year?

$1,006.00

$1,060.00

$1,600.00

$6,000.00

Mrs. Pearson borrowed $1,000.00 for a year at a rate of 6% per year. The total amount she needed to pay off the loan at the end of the year can be calculated by adding the interest to the principal amount. The interest can be found by multiplying the principal amount ($1,000) by the interest rate (6%) and dividing it by 100. Therefore, the interest is $60. Adding the interest to the principal gives us a total of $1,060.00.

Explanation

Mrs. Pearson borrowed $1,000.00 for a year at a rate of 6% per year. The total amount she needed to pay off the loan at the end of the year can be calculated by adding the interest to the principal amount. The interest can be found by multiplying the principal amount ($1,000) by the interest rate (6%) and dividing it by 100. Therefore, the interest is $60. Adding the interest to the principal gives us a total of $1,060.00.

16. Ten years ago, Henry's comic book was worth $2.50. Now it is worth $13. Find the percent of change.

81% increase

80% decrease

42% increase

420% increase

The percent of change can be found by dividing the difference between the final value and the initial value by the initial value, and then multiplying by 100. In this case, the initial value is $2.50 and the final value is $13. The difference is $13 - $2.50 = $10.50. Dividing $10.50 by $2.50 gives 4.2, and multiplying by 100 gives 420%. Therefore, the correct answer is 420% increase.

Explanation

The percent of change can be found by dividing the difference between the final value and the initial value by the initial value, and then multiplying by 100. In this case, the initial value is $2.50 and the final value is $13. The difference is $13 - $2.50 = $10.50. Dividing $10.50 by $2.50 gives 4.2, and multiplying by 100 gives 420%. Therefore, the correct answer is 420% increase.

17. Sally has just purchased a pair of jeans that were originally priced at $38.00. She received a 20% discount and had to pay 7% tax. What was the total amount of her bill?

$28.27

$32.53

$33.06

$48.79

Sally received a 20% discount on the jeans, which means she paid 80% of the original price. So, she paid 0.8 * $38.00 = $30.40 for the jeans. Then, she had to pay 7% tax on this amount. Therefore, the total amount of her bill is $30.40 + 7% of $30.40 = $32.53.

Explanation

Sally received a 20% discount on the jeans, which means she paid 80% of the original price. So, she paid 0.8 * $38.00 = $30.40 for the jeans. Then, she had to pay 7% tax on this amount. Therefore, the total amount of her bill is $30.40 + 7% of $30.40 = $32.53.

18. Jane needs $30.00 to buy her father a present. She has saved 24% of that amount already. How much more money does she need to buy the present?

$6.00

$7.20

$13.20

$22.80

Jane has already saved 24% of the total amount needed, which means she has saved 0.24 * $30.00 = $7.20. To find out how much more money she needs, we subtract the amount she has saved from the total amount needed: $30.00 - $7.20 = $22.80. Therefore, Jane needs $22.80 more to buy the present.

Explanation

Jane has already saved 24% of the total amount needed, which means she has saved 0.24 * $30.00 = $7.20. To find out how much more money she needs, we subtract the amount she has saved from the total amount needed: $30.00 - $7.20 = $22.80. Therefore, Jane needs $22.80 more to buy the present.

19. At the beginning of the season, a baseball player's batting average was .222. At the end of the season, his average was .249. What is the percent of change, rounded to the nearest tenth?

.1216% increase

.121% increase

12.1% increase

12.2% increase

The correct answer is 12.2% increase. To find the percent of change, subtract the initial value (.222) from the final value (.249) and divide by the initial value. Then, multiply by 100 to get the percentage. In this case, (.249 - .222) / .222 * 100 = .027 / .222 * 100 = .1216 * 100 = 12.16%. Rounding to the nearest tenth gives us 12.2% increase.

Explanation

The correct answer is 12.2% increase. To find the percent of change, subtract the initial value (.222) from the final value (.249) and divide by the initial value. Then, multiply by 100 to get the percentage. In this case, (.249 - .222) / .222 * 100 = .027 / .222 * 100 = .1216 * 100 = 12.16%. Rounding to the nearest tenth gives us 12.2% increase.

20. John will need to borrow $20,000 to buy a new car. He will end up paying $3,600 in simple interest after 6 years. What is the interest rate for the loan? (Use the formula I=prt)

3%

9%

92%

5%

John will need to borrow $20,000 to buy a new car. He will end up paying $3,600 in simple interest after 6 years. To find the interest rate, we can use the formula I = prt, where I is the interest, p is the principal amount, r is the interest rate, and t is the time period. Plugging in the given values, we have 3600 = 20000 * r * 6. Solving for r, we get r = 0.03 or 3%. Therefore, the interest rate for the loan is 3%.

Explanation

John will need to borrow $20,000 to buy a new car. He will end up paying $3,600 in simple interest after 6 years. To find the interest rate, we can use the formula I = prt, where I is the interest, p is the principal amount, r is the interest rate, and t is the time period. Plugging in the given values, we have 3600 = 20000 * r * 6. Solving for r, we get r = 0.03 or 3%. Therefore, the interest rate for the loan is 3%.