Respuesta :
Answer:
reject the null hypothesis
Step-by-step explanation:
Total observation = 27+49+24 = 100
Expected Frequency :
Half Pint = 100 × 0.4 = 40
XXX = 100 × 0.4 = 40
Dark night = 100 × 0.2 = 20
The Chi-square goodness-of-fit test can be computed as follows:
       Observed        Expected          [tex]X^2 = \dfrac{(O- E)^2}{E}[/tex]
      Frequency(O)     Frequency (E)
Half- Â Â Â 27 Â Â Â Â Â Â Â Â Â Â Â Â Â Â 40 Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â 4.225 Â Â Â
Pint
XXX Â Â Â 29 Â Â Â Â Â Â Â Â Â Â Â Â Â 40 Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â 3.025
Dark- Â Â Â 24 Â Â Â Â Â Â Â Â Â Â Â Â Â 20 Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â 0.8
night
Total    100             100                 8.05
The test statistics [tex]X^2[/tex] = 8.05
8.05
degree of freedom = n -1
degree of freedom = Â 3 - 1
degree of freedom = Â 2
The p-value can be computed by using the EXCEL FORMULA (=CHIDIST(8.05,2)
p-value = 0.01786
Since the p-value is less than the level of significance, we reject the null hypothesis
Also using the critical value approach from the EXCEL FUNCTION;
critical chi-square  (=CHIINV(0.05,2) = 5.99
[tex]X^2 > 5.99[/tex], therefore, we reject the null hypothesis