Answer:
Step-by-step explanation:
a) Mean = (17 + 11 + 15 + 14 + 16)/5 = 14.6
Standard deviation = √(summation(x - mean)²/n
n = 5
Summation(x - mean)² = (17 - 14.6)^2 + (11 - 14.6)^2 + (15 - 14.6)^2 + (14 - 14.6)^2 + (16 - 14.6)^2 = 21.2
Standard deviation = √(21.2/5 = 2.06
Approximating to 1 decimal place, s = 2
The new data set is
68, 44, 60, 56, 64
Mean = (68 + 44 + 60 + 56 + 64)/5 = 58.4
Summation(x - mean)² = (68 - 58.4)^2 + (44 - 58.4)^2 + (60 - 58.4)^2 + (56 - 58.4)^2 + (64 - 58.4)^2 = 339.2
Standard deviation = √(339.2/5 = 8.24
c) The standard deviation of the new data is 4 times the standard deviation of the previous data
In general, multiplying each data value by the same constant c results in the standard deviation being |c| times as large.
d) s = 2.1 miles
Since 1 mile = 1.6 kilometers, the constant with which we would multiply the given standard deviation is 1.6. Therefore, converting to kilometers, it becomes
1.6 × 2.1 = 3.36 km