Answer:
Mean = $123.8
Range= $72
Variance= $607.344
Standard deviation=$ 24.64
Step by step explanation:
The list of the data of electricity bill on ascending order
$88,$90,$90,$95,$110,$115,$120,$126,$144,$150
Mean = (summation of($88,$90,$90,$95,$110,$115,$120,$126,$144,$150))/10
Mean = 1238/10
Mean = $123.8
Range= highest value- Lowest VA
Range= 150-88
Range= $72
Variance=( (88-123.8)²+(90-123.8)²+(90-123.8)²+(95-123.8)²+(110-123.8)²+(115-123.8)²+(120-123.8)²+(126-123.8)²+(144-123.8)²+(150-123.8)²)/10
Variance= (1281.64+1142.44+1142.44+829.44+190.44+77.44+14.44+4.84+295.84+408.04+686.44)/10
Variance= 6073.44/10
Variance=$ 607.344
Standard deviation= √variance
Standard deviation= √ 607.344
Standard deviation=$ 24.64
