question_answer 9)

The heights of 10 girls were measured in cm and the results are as follows: 135, 150, 139, 128, 151, 132, 146, 149, 143, 141. (i) What is the height of the tallest girl? (ii) What is the height of the shortest girl? (iii) What is the range of the data? (iv) What is the mean height of the girls? (v) How many girls have heights more than the mean height?

Answer:

                (i) Height of the tallest girl = 151 cm (ii) Height of the shortest girl = 128 cm (iii) Range of the data = Highest observation - Lowest observation \[~=\text{151cm}-\text{128cm}=\text{23 cm}\] (iv) \[\text{Mean height of the girls =}\frac{\text{sum of all observations}}{\text{number of observataions}}\] \[=\frac{\begin{align}   & 135+150+139+128+151 \\  & +132+146+149+143+141 \\ \end{align}}{10}=\frac{1414}{10}=141.\text{4 cm}\] (v) 5 girls have heights more than the mean height.