1.924 and 5.77
step 1: find the mean by adding up all the numbers and divide the sum by the number of numbers.
step 2: find the difference between each number and the mean, square the difference
step 3: add up all the results of step 2, divide the sum by (n-1), n is the number of numbers.
step 4: square root the result of step 3.
it is a long process.
