# Expert Answers

Use Venn diagrams to check the validity of the argument
All mathematicians are eccentrics.
All eccentrics are rich.
Therefore, all mathematicians are rich.
2. Suppose you see a car with an advertised price of \$34,300 at \$627.50 per month for 5 years. What is the amount of interest paid?
3. Find the ending balance in an account that opens with \$5,990, earns 10.5% interest compounded monthly, and is held for 25 years. (Round your answer to the nearest cent.)
4. In how many ways can a chairperson and a vice chairperson be selected from a committee of 18 senators?
5. If the principal P = \$500, the rate r = 7 1
2 %, and time t = 1 year, find the following.
(a) What is the amount of interest?
(b) What is the future value?
6. Convert the following credit card rate to the APR.
Oregon, 1 3/4% per month
7. Find the amount of interest and the monthly payment for the loan. Purchase a living room set for \$3,600 at 12% add-on interest for 4 years. (Round your monthly payment to the nearest cent.)
Computing interest due under the add-on interest method is fairly simple. The loan Principal is divided into a number of fixed payments, and each payment is multiplied by the finance charge, to calculate the interest cost to the borrower: Add-On Interest = Principal • Rate • Number of Months in the loan/12
8. Evaluate the expression.
9. If \$730 is invested in an account that earns 8.25%, compounded annually, what will the account balance be after 22 years? (Round your answer to the nearest cent.)
A = 730 (1 + .0825)^22
10. A student is asked to answer 7 out of 12 questions on an exam.
(a) Classify the problem as a permutation, a combination, or neither.
(b) In how many ways can she select the questions to be answered?
11. If you purchase an item for \$1,268 at an interest rate of 9.8%, and you finance it for 1 year, how much is the amount of add-on interest? (Round your answer to the nearest dollar.)
12. In a recent survey of 100 women, the following information was gathered.
51 use shampoo A.
37 use shampoo B.
46 use shampoo C.
13 use shampoos A and B.
11 use shampoos A and C.
20 use shampoos B and C.
9 use all three.
Use the figure to answer the question in the problem.
How many are using shampoos A and C, but not B (Region IV)?
13. A car dealer will sell you a used car for \$5,868 with \$868 down and payments of \$118.33 per month for 60 months. What is the simple interest rate? (Round each answer to the nearest tenth.)
14. Calculate the monthly finance charge for the following credit card transaction. Assume that it takes 10 days for a payment to be received and recorded and that the month is 30 days long. (Round your answer to the nearest cent.)
\$3,000 balance, 21% rate, \$150 payment, adjusted balance method
16. Suppose that you want to purchase a home for \$450,000 with a 30 year mortgage at 6% interest. Suppose that you can put 20% down. Assume that the monthly cost to finance \$1,000 is \$6.00. What is the total amount of interest paid on the 30 year loan?
17. How many skirt-blouse outfits can a woman wear if she has four skirts and six blouses?
18. From a survey of 200 college students, a marketing research company found that 130 students owned iPhones, 75 owned cars, and 65 owned both cars and iPhones.
(a) How many students owned either a car or an iPhone (but not both)?
(b) How many students do not own either a car or an iPhone?
19. Suppose that you want to purchase a home for \$450,000 with a 30 year mortgage at 6% interest. Suppose that you can put 40% down. Assume that the monthly cost to finance \$1,000 is \$6.00. What are the monthly payments?
20. How many permutations are there of the following word
MATHEMATICS
21. A certain lock has three tumblers, and each tumbler can assume seven positions. How many different possibilities are there?