The randomly selected delivery times (in minutes) of two fast food restaurants are as follows.

This table displays the randomly selected delivery times (in minutes) for two fast food restaurants.
Fast Food 1 Fast Food 2
42 40
38 37
37 40
39 41
38 38
40 46
45 41
41 37
40 40
Which of the following statements is false?

(1 point)
Responses

Both fast food restaurants have exactly one modal delivery time of 40 minutes.
Both fast food restaurants have exactly one modal delivery time of 40 minutes.

Both fast food restaurants have the same median delivery time of 40 minutes.
Both fast food restaurants have the same median delivery time of 40 minutes.

Neither data set contains an outlier.
Neither data set contains an outlier.

Both fast food restaurants have the same mean delivery time of 40 minutes.

1 answer

Let's analyze the delivery times of both fast food restaurants to determine which statement is false.

Delivery Times:

  • Fast Food 1: 42, 38, 37, 39, 38, 40, 45, 41, 40
  • Fast Food 2: 40, 37, 40, 41, 38, 46, 41, 40, 40

Finding the mode:

  • Fast Food 1:

    • Frequencies: 37 (1), 38 (2), 39 (1), 40 (2), 41 (1), 42 (1), 45 (1)
    • Mode: 38 and 40 (both appear 2 times) - thus, Fast Food 1 does not have exactly one modal delivery time.
  • Fast Food 2:

    • Frequencies: 37 (1), 38 (1), 40 (5), 41 (2), 46 (1)
    • Mode: 40 (appears 5 times)

Finding the median:

  • Fast Food 1: Sorted delivery times: 37, 38, 38, 39, 40, 40, 41, 42, 45

    • Median: 40 (5th value)
  • Fast Food 2: Sorted delivery times: 37, 38, 40, 40, 40, 40, 41, 41, 46

    • Median: 40 (5th value)

So, both restaurants have the same median delivery time of 40 minutes.

Finding outliers: For this analysis, we can use the IQR (Interquartile Range) method:

  1. Fast Food 1:

    • Q1 = 38, Q3 = 41
    • IQR = Q3 - Q1 = 41 - 38 = 3
    • Lower Bound = Q1 - 1.5 * IQR = 38 - 4.5 = 33.5
    • Upper Bound = Q3 + 1.5 * IQR = 41 + 4.5 = 45.5
    • No outliers (all values are within the bounds).
  2. Fast Food 2:

    • Q1 = 38, Q3 = 40
    • IQR = Q3 - Q1 = 40 - 38 = 2
    • Lower Bound = 38 - 3 = 35
    • Upper Bound = 40 + 3 = 43
    • No outliers (all values are within the bounds).

Finding the mean:

  • Fast Food 1 Mean: \((42 + 38 + 37 + 39 + 38 + 40 + 45 + 41 + 40) / 9 = 40.33\)

  • Fast Food 2 Mean: \((40 + 37 + 40 + 41 + 38 + 46 + 41 + 40 + 40) / 9 = 40.33\)

Now evaluating the statements:

  1. Both have exactly one modal delivery time - FALSE for Fast Food 1.
  2. Both have the same median delivery time of 40 minutes - TRUE.
  3. Neither dataset contains an outlier - TRUE.
  4. Both have the same mean delivery time - TRUE.

Thus, the false statement is:

"Both fast food restaurants have exactly one modal delivery time of 40 minutes."