1. x 9 8 6 4 2 1 30 6 =5 +4 +3 +1 -3 -4 0 4 3 1 1 3 4 16 6 =2.67

2. 80 0 0 0 0 0 0 0 86 84 82 80 78 76 74 6 4 2 0 2 4 6 110 100 90 80 70 60 50 30 20 10 0 20 30 XX X =0 =24 =120 =80 R=0 R=12 R=60 MD=0 MD=12 MD=17.14

3. Variance Sum of the squared deviations from the mean x 9 8 6 4 2 1 +4 +3 +1 -3 -4 16 9 1 1 9 =52 52 6 =8.67

4. 3 5 5 7 4 4 6 6 XX 2 0 0 2 4 0 0 4 1 1 1 1 1 1 1 1 =5 MD =1 s2s2 =2s2s2 =1

5. x 9 8 6 4 2 1 +4 +3 +1 -3 -4 16 9 1 1 9 =52 2.94

6. 9 8 6 4 2 1 81 64 36 16 4 1 202 6 -25 33.67-25 =8.67 x2x2 mean=5

7. For the following numbers calculate the range, mean deviation, the variance and standard deviation. 4 17 12 9 6 10 1 5 9 3 =7.6 3.6 9.4 4.4 1.4 1.6 2.4 6.6 2.6 1.4 4.6 38 12.96 88.36 19.36 1.96 2.56 5.76 43.56 6.76 1.96 21.16 204.4