Answer: -9n+20
This is the same as 20-9n
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Explanation:
The jump from 11 to 2 is "minus 9"
The jump from 2 to -7 is also "minus 9".
Assuming this pattern continues on, we have an arithmetic sequence with
- a = 11 = first term
- d = -9 = common difference
The nth term can be found like so

Let's check the answer by trying n = 3

This shows the third term is -7, which matches what the original sequence shows. The answer is partially confirmed. I'll let you check the other values of n. You should get 11 when trying n = 1, and you should get 2 when trying n = 2.
The formula for the volume of a right circular cone is V =

. In solving for the volume of the first french fries cones V =

= 75.398

. In solving for the height of the second french fries cones with a new radius of 4, the formula is rearranged to h =

=

= 1.5 in or inches. The height of the new cones will be 1.5 inches.
The answer is 11 1/4 or 11.75