How to Use Sample Variance:
1. Add the numbers in your given data set.
2. Square your answer. And divide by the number of values there are.
3. Take your set of original numbers from Step 1, and square them individually this time.
4. Subtract the amount in Step 2 from Step 3. Set this number aside for a moment.
5. Subtract 1 from the number of values in your data set.
6. Divide the number in Step 4 by the number in Step 5. This gives you the variance.
Sample Math Problems
1. [3, 4, 9, 11, 17, 19]
Answer:
a. 3+4+9+11+17+19 = 63
b. 63(63) = 3969/6 = 661.5
c. 9 + 16 + 81 + 121 + 289 + 361 = 877
d. 877 - 661.5 = 215.5
e. 6-1 = 5
f. 215.5/5 = 43.1; Answer: 43.1
2. [6, 27, 15, 7, 19, 13]
Answer:
a. 6+27+15+7+19+13 = 87
b. 87(87) = 7569/6 = 1261.5
c. 6(6) + 27(27) + 15(15) + 7(7) + 19(19) + 13(13) = 1569
d. 1569 - 1261.5 = 307.5
e. 6-1 = 5
f. 307.5/5 = 61.5; Answer: 61.5
3. [2, 3, 5, 7, 11, 13]
Solution:
a. 2+3+5+7+11+13 = 41
b. 41(41) = 1681/6 = 280.17
c. 2(2) + 3(3) + 5(5) + 7(7) + 11(11) + 13(13) = 377
d. 377 - 280.17 = 96.83
e. 6-1 = 5
f. 96.83/5 = 19.366; Answer: 19.366
4. [17, 19, 23, 29, 31, 37]
Solution:
a. 17+19+23+29+31+37 = 156
b. 156(156) = 24336/6 = 4056
c. 17(17) + 19(19) + 23(23) + 29(29) + 31(31) + 37(37) = 4350
d. 4350 - 4056 = 294
e. 6-1 = 5
f. 294/5 = 58.8; Answer: 58.8
