Question

The equation C(l) = l3 – l2 + l + 2.5 models the cost to mail a package as a function of its length. To the nearest quarter inch, approximately what is the length of a package that costs $11.00 to mail? Enter your answer as a decimal.​

Answer 1

2.75

Explanation:

Answer 2

2.25

Explanation:

Given the cost model:

C(l) = l3 – l2 + l + 2.5

l = Length fo package

The length of a package that cost $11.00

11 = l³ - l² + l + 2.5

From the table given :

Length of mail which cost $11 will just be slightly greater Than 2 as the cost of 2 length mail cost 8.50

Taking l as 2.20

2.2^3 - 2.2^2 + 2.2 + 2.50 = 10.508

Taking a slightly higher value :

Put l = 2.25

2.25^3 - 2.25^2 + 2.25 + 2.50 = 11.078

Ww can conclude that the length of mail would be 2.25