A communications company has developed three new designs for a cell phone. To evaluate consumer response, a sample of n = 120 college students is selected and each student is given all three phones to use for one week. At the end of the week, the students must identify which of the three designs they prefer. The distribution of preference is as follows: Design 1 Design 2 Design 3
54 38 28

Required:
Do the results indicate any significant preferences among the three designs?

There is significant preference among the 3 designs

Step-by-step explanation:

Given :

Design 1 Design 2 Design 3

54 38 28

H0 : no significant preference among the 3 designs

H1 : The preference among the designs are different

To test, we use the Chisquare test for independence ;

χ² = (observed - Expected)² / Expected

The sample size, n = 120

Expected = 120 / number of designs = 120 / 3 = 40

(54-40)^2/ 40 + (38 - 40)² / 40 + (28 - 40)² / 40

= 4.9 + 0.1 + 3.6

= 8.6

The Chisquare critical value at 95% = 5.99

Since ;

|χ² critical| < χ² statistic ; we reject the null and conclude that there is significant preference among the 3 designs

d i think

step-by-step explanation:

so, converting firstly the mixed fractions to improper fractions and then "adding".