In 1999 the stock market took big swings up and down. A survey of 997 adult investors asked how often they tracked their portfolio. The table shows the investor responses the probability that an adult investor tracks his or her portfolio daily?
How frequently? Response Daily
222
Weekly
278
Monthly
277
Couple times a year
150
Don't track
70
To calculate the probability that an adult investor tracks their portfolio daily, we divide the number of investors who track their portfolio daily (222) by the total number of adult investors surveyed (997).
Probability = Number of investors who track their portfolio daily / Total number of adult investors surveyed
Probability = 222 / 997
The probability that an adult investor tracks their portfolio daily is approximately 0.222 or 22.2%.