Question

Mrs. Goodman's physics class built different-shaped parachutes to see which shapes were more effective. The students tested the parachutes by dropping them from a height of 20 feet and timing the fall. They calculated the summary below:

Mean Std Dev Min Q1 Median Q3 Max
4.6 secs 0.4 sec 2.3 secs 3.1 secs 4.2 secs 5.5 secs 6.4 secs
The students want to see what happens to their times when they drop the parachutes from 32 feet. They find that the time of every drop is increased by 2 seconds. Find the new mean and standard deviation.
A. Mean, 6.6 seconds; standard deviation, 0.4 second
B. Mean, 2.6 seconds; standard deviation, 0.4 second
C. Mean, 6.6 seconds; standard deviation, 2.4 seconds
D. Mean, 4.6 seconds; standard deviation, 2.4 seconds

Answer 1

The new mean is 6.6 seconds and the standard deviation remains 0.4 seconds.

Step-by-step explanation:

To find the new mean and standard deviation, we can add 2 seconds to each observation in the summary statistics. The new mean is obtained by adding 2 seconds to the original mean of 4.6 seconds, giving us a new mean of 6.6 seconds. The new standard deviation remains the same at 0.4 seconds.