4. Luke can purchase a 12-pound item from several

different retailers. Which of the following is the
best buy?
A Buy online for $15 plus pay shipping and
handling costs of $0.79 per pound.
B Buy online for $17 plus pay shipping and
handling costs of $0.69 per pound.
C Buy at a local store where the item’s price is
$24.99, and use a $3-off coupon.
D Buy at a local store where the item’s regular
price is $22.50 and it is on sale for 10% off.

3. Each year on the same day, Susan deposits $275
into a savings account that earns simple interest at
a rate of 4.5%. She makes no withdrawals. In 5
years, how much interest does the account earn?
A $12.38
B $61.90
C $99.01
D $185.64

I just need an equation for me to solve both of these questions please! Thanks!

Sure! Let's go through each question and set up an equation to find the answer:

4. For this question, we need to compare the total cost of purchasing a 12-pound item from each option.

Option A:
Total cost = $15 (purchase price) + $0.79 (shipping cost per pound) x 12 (pounds)

Option B:
Total cost = $17 (purchase price) + $0.69 (shipping cost per pound) x 12 (pounds)

Option C:
Total cost = $24.99 (purchase price) - $3 (coupon discount)

Option D:
Total cost = $22.50 (regular price) - 10% (discount) = 0.9 (discounted price)

You can calculate the total cost for each option and compare to find the best buy based on the lowest total cost.

3. To calculate the interest earned by Susan's savings account after 5 years, we need to use the formula for simple interest:

Interest = Principal x Rate x Time

Here, the principal is the amount Susan deposits each year ($275), the rate is the interest rate (4.5% or 0.045), and the time is the number of years (5).

So the equation to find the interest earned would be:

Interest = $275 x 0.045 x 5

You can solve this equation to find the amount of interest earned in the account after 5 years.