9.8 , 9.8 , 9.9 , 9.9 , 10.0 , 10.0 , 10.1 , 10.5
The mean and the standard deviation of the 8 numbers shown above is 10 and 0.212 respectively. What percent of the 8 numbers are within 1 standard deviation of the mean?	Choose the correct option:
A) 90.5%	B) 87.5%	C) 80.5%	D) 77.5%	E) 70.5%
Within 1 standard deviation of the mean- means in the range {mean-1*sd; mean+1*sd} = {10-1*0.212; 10+0.3} = {9.788; 10.212}.   From the 8 listed numbers, 7 are within this range so 6/8=87.5%.   Answer: 87.5%.
<result>B</result>
9.8 , 9.8 , 9.9 , 9.9 , 10.0 , 10.0 , 10.1 , 10.5
The mean and the standard deviation of the 8 numbers shown above is 10 and 0.212 respectively. What percent of the 8 numbers are within 1 standard deviation of the mean?