Question

The height of 7 students are listed.


The mean height of the students before and after increasing the height by 2 cm is

• A. 166 cm, 170 cm
• B. 161.67 cm, 171,26 cm
• C. 162 cm, 164 cm

Answer 1

The correct option is C 162 cm, 164 cm

The given data set is

150, 153, 172, 168, 170, 156, 165

Mean = $\frac{sumofalldata}{numberofdata}$

= $\frac{150+153+172+168+170+156+165}{7}$

= $\frac{1134}{7}$

= 162

= 162

After each data is increased by 2, the new data set is

152, 155, 174, 170, 172, 158, 167

Mean = $\frac{sumofalldata}{numberofdata}$

= $\frac{152+155+174+170+172+158+167}{7}$

= $\frac{1148}{7}$

= 164

Hence, the mean height of the data before and after increasing the height are 162 cm and 164 cm, respectively.