第3章数学モデル

Casey deposited $1,450 in a bank account with interest rate 4%. How much interest was earned in two years?

Terrence deposited $5,720 in a bank account with interest rate 6%. How much interest was earned in 4 years?

Robin deposited $31,000 in a bank account with interest rate 5.2%. How much interest was earned in 3 years?

Carleen deposited $16,400 in a bank account with interest rate 3.9%. How much interest was earned in 8 years?

Hilaria borrowed $8,000 from her grandfather to pay for college. Five years later, she paid him back the $8,000, plus $1,200 interest. What was the rate of interest?

Kenneth loaned his niece $1,200 to buy a computer. Two years later, she paid him back the $1,200, plus $96 interest. What was the rate of interest?

Lebron loaned his daughter $20,000 to help her buy a condominium. When she sold the condominium four years later, she paid him the $20,000, plus $3,000 interest. What was the rate of interest?

Pablo borrowed $50,000 to start a business. Three years later, he repaid the $50,000, plus $9,375 interest. What was the rate of interest?

In 10 years, a bank account that paid 5.25% earned $18,375 interest. What was the principal of the account?

In 25 years, a bond that paid 4.75% earned $2,375 interest. What was the principal of the bond?

Joshua’s computer loan statement said he would pay $1,244.34 in interest for a 3-year loan at 12.4%. How much did Joshua borrow to buy the computer?

Margaret’s car loan statement said she would pay $7,683.20 in interest for a 5-year loan at 9.8%. How much did Margaret borrow to buy the car?

Perla bought a cell phone that was on sale for $50 off. The original price of the cell phone was $189.

Sophie saw a dress she liked on sale for $15 off. The original price of the dress was $96.

Rick wants to buy a tool set with original price $165. Next week the tool set will be on sale for $40 off.

Angelo’s store is having a sale on televisions. One television, with original price $859, is selling for $125 off.

Janelle bought a beach chair on sale at 60% off. The original price was $44.95.

Errol bought a skateboard helmet on sale at 40% off. The original price was $49.95.

Kathy wants to buy a camera that lists for $389. The camera is on sale with a 33% discount.

Colleen bought a suit that was discounted 25% from an original price of $245.

Erys bought a treadmill on sale at 35% off. The original price was $949.95 (round to the nearest cent.)

Jay bought a guitar on sale at 45% off. The original price was $514.75 (round to the nearest cent.)

Larry and Donna bought a sofa at the sale price of $1,344. The original price of the sofa was $1,920.

Hiroshi bought a lawnmower at the sale price of $240. The original price of the lawnmower is $300.

Patty bought a baby stroller on sale for $301.75. The original price of the stroller was $355.

Bill found a book he wanted on sale for $20.80. The original price of the book was $32.

Nikki bought a patio set on sale for $480. The original price was $850. To the nearest tenth of a percent, what was the rate of discount?

Stella bought a dinette set on sale for $725. The original price was $1,299. To the nearest tenth of a percent, what was the rate of discount?

Daria bought a bracelet at original cost $16 to sell in her handicraft store. She marked the price up 45%.

Regina bought a handmade quilt at original cost $120 to sell in her quilt store. She marked the price up 55%.

Tom paid $0.60 a pound for tomatoes to sell at his produce store. He added a 33% mark-up.

Flora paid her supplier $0.74 a stem for roses to sell at her flower shop. She added an 85% mark-up.

Alan bought a used bicycle for $115. After re-conditioning it, he added 225% mark-up and then advertised it for sale.

Michael bought a classic car for $8,500. He restored it, then added 150% mark-up before advertising it for sale.