Question

Because colas tend to replace healthier beverages and colas contain caffeine and phosphoric acid, researchers wanted to know whether cola consumption is associated with lower bone mineral density in women. The accompanying data lists the typical number of cans of cola consumed in a week and the femoral neck bone mineral density for a sample of 15 women. Complete parts (a) through (f) below.

Data Table

                                                       Colas per week     Bone Mineral Density (g/cm3 )

0                                         0.908

1                                         0.867

1                                         0.880

2                                         0.841

2                                         0.852

2                                         0.834

2                                         0.834

3                                         0.814

5                                         0.757

5                                         0.762

5                                         0.758

5                                         0.757

6                                         0.726

7                                         0.708

8                                         0.676

(a) Find the least-squares regression line treating cola consumption per week as the explanatory variable.

^y= ______________x +_____________(Round to three decimal places as needed.)

(b) Interpret the slope. Select the correct choice below and, if necessary, fill in the answer box to complete your choice.

A. For a bone density of 0 g / cm3 , the number of colas consumed is predicted to be __________ . (Round to three decimal places as needed.)

B. For every cola consumed per week, the bone density decreases by__________g/cm³ on average. (Round to three decimal places as needed.)

C. For 0 colas consumed in a week, the bone density is predicted to be_________g / cm . (Round to three decimal places as needed.)

D. For every unit increase in bone density, the number of colas decreases by average. (Round to three decimal places as needed.)

E. It is not appropriate to interpret the slope.

(c) Interpret the y-intercept. Select the correct choice below and, if necessary, fill in the answer box to complete your choice.

A. For 0 colas consumed in a week, the bone density is predicted to be  ___________ g / cm3 . (Round to three decimal places as needed.)

B. For every cola consumed per week, the bone density decreases by _________g/cm³ on average. (Round to three decimal places as needed.)

C. For every unit increase in bone density, the number of colas decreases by __________average. (Round to three decimal places as needed.)

D. For a bone density of 0 g / cm3 , the number of colas consumed is predicted to be ________in (Round to three decimal places as needed.)

E. It is not appropriate to interpret the y-intercept.

Answer 1