Question

Look at the data.

Time (min)
Depth (cm)
2
8
4
15
6
29
8
37
10
39
12
49
14
55
A person measured the depth of water in a bathtub at two-minute intervals after the
tap was turned on. Use the line of best fit to find the amount of water, in cm, present
initially in the bathtub. Round to the nearest integer.

Answer 1

2 cm

Explanation:

Data

Time (min) Depth (cm)

2 8

4 15

6 29

8 37

10 39

12 49

14 55

The line of best fit to find the amount of water is:

y = 3.9107x + 1.8571

(I used Excel to get it, you can use a calculator or similar programs if you want to)

In the equation, y represents depth (in cm) and x represents time (in min).

The amount of water, in cm, present initially in the bathtub is found at time equal to zero. Replacing x = 0 in the equation, we get:

y = 3.9107(0) + 1.8571

y = 1.8571 ≈ 2 cm