In this case, we'll have to carry out several steps to find the solution.
Step 01:
Data
mean = 51 minutes
standard deviation = 5 minutes
interval 68% = ?
Step 02:
Range for 68% of the data values:
51 + 5 = 56
51 - 5 = 46
68% of the data values will fall within 1 standard deviation of the mean, from 46 to 56.
The answer is:
( 46 , 56 )
