Let's write the given results:
Color Frequency
Blue 12
Yellow 11
Red 17
Green 16
White 19
Orange 15
The expected frequency of each color must be,
Thus,
Color Frequency Expected (Recored - Expected)^2/Expected
Blue 12 15 0.60
Yellow 11 15 1.07
Red 17 15 0.27
Green 16 15 0.07
White 19 15 1.07
Orange 15 15 0.00
Chi-Square (χ2)= 3.08
Degree of freedom = 6 - 1 = 5.
Alpha level (α) = 0.10
Thus, it will give you a p-value of 0.6897.
Since 0.6897 > 0.10, we fail to reject the null.
Conclusion: There is no sufficient evidence to support the student's claim that the spinner is defective.