calculate the mean, median, the mode and is the data symmetrical, positively skewed or negetively skewed?

Question

in the small village of moloto, a population of homeowners were asked that their electricity bills were previous month. the following table summarises the result. ( eletricity bills: in rands of 42 population house holds. 120 170 145 155 170 125 172 125 185 140 145 140 130 615 135 165 146 140 149 125 160 136 155 148 146 130 128 124 110 163 150 521 135 145 180 120 165 145 140 120 125 120 2.1.1 calculate the mean ( correct decimal places) and show all the steps. 2.1.2 calculate the median 2.1.3 calculate the mode 2.1.4 is your data symmetrical, positively skewed or negetively skewed? 2.2 calculate 2.2.1 the variance ( correct to 3 decimal place) 2.2.2 the standard deviation ( correct to 3 decimal places) 2.2.3 the interquartile range 2.2.4 the semi- interquartile range 2.3 do the data contain and outlier (s)? Explain your answer. 2.4 which is better measure of the spread of the data- the standard deviation or the interquartile range? explain your answer. 2.5 use the class intervals 110 less or equal x less or equal to 119, 120 less or equal x less or equal to 129, 130 less equal x less equal to 139 and so on construct a frequency table for the electricity bill in of the population of 42 households. 2.6 using the same frgequency table in 2.5 and class boundaries ( intervals) construct a histogram to represent the electricity bills. 2.7 what percentage of households spends less than R150 per month of electricity? Please Mr Rod # it like that Mr Rob no mistakes thanks

Comments

Please check your data. I think 615 should be 165 or 156, and 521 should be 125. If these are errors, it will seriously affect the answers. Please edit and resubmit or comment if they are not errors.

Answer 1

The first step is to order the data:

(split into quartiles)

110, 120, 120, 120, 120, 124, 125, 125, 125, 125,

128, 

130, 130, 135, 135, 136, 140, 140, 140, 140, 145,

145, 145, 145, 146, 146, 148, 149, 150, 155, 155,

160, 

163, 165, 165, 170, 170, 172, 180, 185, 521(?), 615(?).

mean=163.4047619, 143.175 (if outliers are ignored).

Median=145.

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