Question

A kayak rental company charges $25.00 to rent a kayak and $3.50 for each half hour it is used.

Which linear function best represents the total cost of renting a kayak for 4 hours?


r (t) = 3.50t + 25
r(4) = 39



r (t) = 25t +3.5
R(8) = 203.5



r(t) = 25t + 3.5
r(4) = 103.5



r(t) = 3.50t +25
r(8) = 53

Answer 1

The Answer would be D.

r(t) = 3.50t +25

r(8) = 53

Explanation:

The Rental Company charges a fixed price of $25 to rent the kayak, as well as an additional $3.50 for each half hour. So the only variable we are looking at would be the amount of time the kayak was rented. We can model this question with the following equation.

`f(x) = 25 + 3.50x`

with x being the time the kayak was rented in 30 min intervals. Since the kayak was rented for 4 hours we can multiply this by 2 to get 8 (30 min intervals). Now we can plug this into the formula and solve it.

`f(8) = 25 + 3.50(8)`

`f(8) = 25+  28`

`f(8) = 53`

So to rent the kayak for 4 hours it would cost $53

Answer 2

Option D (r(t) = 3.50t +25 ; r(8) = 53)

Explanation:

The fixed cost to rent the kayak $25. This is the cost which remains fixed irrespective of the usage of the kayak. The variable cost of using the kayak is the cost which depends on the usage of the kayak. It is mentioned that the kayak is used for 4 hours and the company charges $3.5 for every half hour. The cost function is given by:

r(t) = 25 + 3.5t ; there r is the total cost of using the kayak and t is the number of half-hours the kayak is used.

4 hours means that there are 8 half-hours. Therefore, t=8. Put t=8 in r(t).

r(8) = 25 + 3.5*(8) = 25 + 28 = 53.

Therefore, Option D is the correct answer!!!