railway RRB Technician Grade 1 Mock Test 2024 Mathematics Statistics Variance and Standard Deviation
Which formula is used to determine the value of the standard deviation of ungrouped data?
1
\(\sqrt {\frac{{\sum {D^2}}}{N}} \)
2
\( {\frac{{\sum {D^2}}}{N}} \)
3
\(\sqrt {\frac{{\sum {N}}}{D^2}} \)
4
\( {\frac{{\sum {D}}}{N}} \)