Answer:
Adding 5 seconds would give
Mean= X`= 258.8 seconds
Standard Deviation=S= 82.8 seconds
The standard deviation remains the same.
Mean z= 0
Standard Deviation z= 1
Step-by-step explanation:
Mean= 4.23 minutes,
Standard Deviation= 1.38 minutes
He wants to add 5 seconds of silence between songs,
So we will convert these minutes into seconds
Mean= 4.23 minutes * 60= 253.8 seconds
Standard Deviation= 1.38 minutes* 60= 82.8 seconds
Adding 5 seconds would give
Mean= X`= 4.23 minutes * 60 +5 = 258.8 seconds
Standard Deviation=S= 1.38 minutes* 60= 82.8 seconds
The standard deviation remains the same.
b. Transforming into z- scores would give
Mean z= x`-u/s= 4.23-4.23/1.38= 0
Standard Deviation z= s/s= 1.38/1.38= 1
This is because changing into z- scores is simply a linear transformation.