Question 9.301

35. Mutual Fund Performance. Business Insider reported that 58% of mutual funds underperformed in 2013, against the Standard and Poor 500 benchmark. Suppose a random sample of 100 mutual funds showed 67 that had underperformed. Test whether the population proportion has increased, using level of significance .

9.5.35

Both and , so the conditions for using the test for proportions are met.

Step 1

We reject if the .

Step 2

Step 3

Step 4 The is , so we reject . There is evidence at level of significance that the population proportion of mutual funds that underperform has increased from 58%.