Question

THe cost of a hamburger is $2.50. Each additional hamburger cost $2.00. Sully wrote this explicit rule to explain the sequence of costs: f(n) = 2 + 2.5(n-1). Using the rule, he found the cost of 12 hamburgers to be 29.50. Is this number correct?

Answer 1

yes, it is correct

you just plug in the 12 where the n is

Answer 2

Yes, the number is correct.

Explanation:

The cost of a hamburger is $2.50.

Each additional hamburger cost $2.00.

Sully wrote this explicit rule to explain the sequence of costs:

`f(n) = 2+2.5(n-1)`

Using the rule, he found the cost of 12 hamburgers to be 29.50.

Lets check by putting n = 12.

`f(12) = 2+2.5(12-1)`

=
`2+2.5(11)`

=
`2+27.5`

= $29.50

So, yes Sully is correct.