A computer store is currently selling 3 brands of laptops. The table below is a

Question

A computer store is currently selling 3 brands of laptops. The table below is a breakdown of historical sales proportions of three laptop brands and observed sales of each brand for the current month. A manager of the store wants to determine whether the current sales are similar to those he has seen in the past. (=0.05)

Brands

Historical %

Current

Toshiba

35

37

Sony

45

50

Lenovo

20

33

1. What is the correct calculated value for the appropriate test?

a. 78.97

b. 3.95

c. 0.89

d. 4.27

e. 15.78

2. What is the appropriate managerial decision?

a. Reject the null hypothesis

b. Do not reject the null hypothesis.

c. There is a difference between historical and current sales of each brand.

d. Current sales appear to be similar to the past for each brand.

e. There is not enough information to make a conclusion

Brands

Historical %

Current

Toshiba

35

37

Sony

45

50

Lenovo

20

33

Explanation / Answer

applying chi square test of goodness of fit on above:

1) therefore option d . 4.27 is correct

2) b. Do not reject the null hypothesis.

observed Expected Chi square Type Probability O E=total*p =(O-E)^2/E Toshiba 0.350 37.000 42.00 0.60 Sony 0.450 50.000 54.00 0.30 Lenovo 0.200 33.000 24.00 3.38 1 120 120 4.2665

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.