The data set shown by the dot plot represents the ages of the boys on a baseball team.

The dot plot shows one dot above 10, two dots above 11, two dots above 12, three dots above 13, and one dot above 14.

A new boy, who is 8, has joined the baseball team since the dot plot has been made.

Determine whether the value of each statistic, for the ages of the boys, will increase, stay the same, or decrease once the age of the new boy is added to the data set. Select Increase, Stay the Same, or Decrease for each statistic.
Increase Stay the Same Decrease
Mean
Median
Standard Deviation

User Icon for Bot GPT 4-o mini Bot GPT 4-o mini answered
2 hours ago

To determine how the addition of the new boy (age 8) affects the mean, median, and standard deviation of the ages of the boys on the baseball team, we first summarize the current data from the dot plot.

Current ages represented by the dot plot:

  • 10: 1 boy
  • 11: 2 boys
  • 12: 2 boys
  • 13: 3 boys
  • 14: 1 boy

Current totals:

  • Ages: 10, 11, 11, 12, 12, 13, 13, 13, 14
  • Total number of boys = 1 + 2 + 2 + 3 + 1 = 9
  • Total age sum = 10 + 11 + 11 + 12 + 12 + 13 + 13 + 13 + 14 = 10 + 22 + 36 + 14 = 121

Adding the new boy (age 8):

  • New total number of boys = 9 + 1 = 10
  • New total age sum = 121 + 8 = 129

Calculating the statistics:

  1. Mean:

    • Current Mean = Total age / Number of boys = 121 / 9 ≈ 13.44
    • New Mean = New total age / New number of boys = 129 / 10 = 12.9
    • Result: Decrease
  2. Median:

    • Current ages (sorted): 10, 11, 11, 12, 12, 13, 13, 13, 14
    • Current Median (5th value) = 12
    • New ages including the new boy: 8, 10, 11, 11, 12, 12, 13, 13, 13, 14 (sorted)
    • New Median (average of the 5th and 6th values) = (12 + 12) / 2 = 12
    • Result: Stay the Same
  3. Standard Deviation:

    • Adding a value that is lower than the existing mean (most of the data is above 8) will increase the spread of the data.
    • The standard deviation measures how much the ages vary from the mean, and since 8 is quite far from the previous mean and will introduce more spread, the standard deviation will increase.
    • Result: Increase

Final Summary:

  • Mean: Decrease
  • Median: Stay the Same
  • Standard Deviation: Increase