In a sample of 200 racquetball players, 120 indicated they prefer Penn racquetballs, 75 favored ...

In a sample of 200 racquetball players, 120 indicated they prefer Penn racquetballs, 75 favored Ektelon, and 5 were indifferent. We want to use the sign test to determine if there is evidence of a significant difference in the preferences for the two types of racquetballs. Hint: Use the continuity correction factor.
 a. Provide the hypotheses to be tested.
  b. Compute the mean.
  c. Compute the standard deviation.
  d.. At a 5 level of significance, test to determine if there is evidence of a significant difference in the preferences for the two types of racquetballs.