Lesson 5 Money Matters Develop Understanding

Ready

Identify the type of function represented in each table as either linear, exponential, quadratic, or unknown.

1.

$x$	$f (x)$
$1$	$8$
$2$	$17$
$3$	$32$
$4$	$53$
$5$	$80$

2.

$x$	$f (x)$
$1$	$3$
$2$	$- 12$
$3$	$- 27$
$4$	$- 42$
$5$	$- 57$

3.

$x$	$f (x)$
$1$	$- 50$
$2$	$- 37$
$3$	$- 26$
$4$	$- 17$
$5$	$- 10$

4.

$x$	$f (x)$
$1$	$- 7$
$2$	$- 21$
$3$	$- 63$
$4$	$- 189$
$5$	$- 567$

5.

$x$	$f (x)$
$1$	$0.5$
$2$	$0.25$
$3$	$0.125$
$4$	$0.0625$
$5$	$0.03125$

6.

$x$	$f (x)$
$1$	$- 3$
$2$	$- 2.1$
$3$	$- 1.2$
$4$	$- 0.3$
$5$	$0.6$

7.

If you graphed #2 and #6 and connected the points, what basic shape would you see?

8.

If you found the first difference at each step in #1 and #4, what would you know about the two functions?

9.

Find the second difference in #4 and #5. What do you notice about the second difference in each of those two functions?

10.

What do you notice about the second difference in #1? What does this tell you about the function?

Set

Recall the equation for compound interest you used in class today:

$A = P {(1 + \frac{r}{n})}^{n t}$

11.

Calculate the amount of money in an account after $15 years$ if $$ 7,000$ is deposited at $6 %$ annual interest compounded as follows:

a.

annually

b.

semiannually

c.

quarterly

d.

daily (Use $n = 365$ )  

12.

How much money will be in an account at the end of $34 years$ if $$ 17,000$ is deposited at $12 %$ annual interest compounded as follows?  

a.

annually

b.

semiannually

c.

quarterly

d.

daily (Use $n = 365$ )  

13.

When you were born, your grandfather invested $$ 2,000$ for you at $12.5 %$ interest compounded daily. No one told you about it until you were $50 years$ old. Would you be a millionaire on the day you turned $50$ ? Justify your answer.

14.

If Tanisha opens an account with $$ 5,000$ at an interest rate of $7 %$ compounded weekly (Use $52 \frac{weeks}{year}$ ), how long will it take for her account to be worth $$ 20,000$ ?

15.

Your parents plan to purchase a new car for you on your $16 th$ birthday. They always pay cash but they are good planners. The car costs $$ 18,000$ . A long time ago, they deposited $$ 6,000$ in an account that paid $8.5 %$ interest. The account will have $$ 18,000$ in it by your birthday. How old were you when they created the account?

Go

Solve the following equations by taking the appropriate log of each side.

16.

$10^{x} = 3,162$

17.

$10^{x} = 6$

18.

$10^{x} = 436,516$

19.

$7^{x} = 250$

20.

$6^{x} = 592$

21.

$13^{x} = 1,345$

22.

$5^{x + 4} = 1,783$

23.

$3^{2 x + 7} = 51,285$

24.

$2^{5 x - 4} = 293, 185$