To find the standard deviation, the first step is to find the mean of all the numbers, so add them all and divide by the amount of numbers.
All those numbers added together equal 943. 943 divided by 40 equals 23.575.
The second step is to subtract the mean from every provided number and square the result.
Your set of numbers after this will be(all rounded to the nearest tenth):
423.3; 383.2; 158.1; 73.5; 57.4; 43.2; 2.5; 417.2; 180.2; 57.4; 91.7; 0.2; 2.0; 73.5; 5.9; 11.7; 88.8; 29.4; 130.5; 417.2; 111.8; 6.6; 2.5; 184.3; 134.0; 242.6; 269.8; 71.0; 5.9; 11.7; 55.1; 108.7; 29.4; 43.2; 242.6; 0.2; 31.1; 548.7; 88.8; 108.7
The third step is to find the mean of those numbers. All those numbers added together equals 4,943.6. 4,943.6 divided by 40 equals 123.59.
The fourth step is to find the square root of the recently discovered mean. The square root of 123.59 is
11.1171039394
and you can round that to whatever is required by the question.
Hope I helped! That was a fun challenge!
