Freight car loadings over an 18-week period at a busy port are as follows:

Week

Number

Week

Number

Week

Number

1

410

7

460

13

540

2

420

8

480

14

550

3

430

9

500

15

570

4

420

10

490

16

580

5

430

11

510

17

590

6

440

12

530

18

600

a.

Determine a linear trend line for expected freight car loadings. (Round your intermediate calculations and final answers to 2 decimal places.)

= [removed] + [removed] t

b.

Use the above trend equation to predict expected loadings for Weeks 20 & 21. (Round your final answers to 2 decimal places.)

The forecasted demand for Week 20 is [removed] and for Week 21 is [removed] .

c.

The manager intends to install new equipment when the volume exceeds 990 loadings per week. Assuming the current trend continues, in which week (at the earliest) should the loading volume reach that level? ( Use the rounded answers, as required, from any previous part of this problem. Do not round any other intermediate calculations. Round your final answer to 2 decimal places.)

It should reach 990 loadings in Week [removed] .