Question

The average height of 13 girls in a class is $144\frac{8}{13}$ cm. The average height of 11 boys in the class is $169\frac{5}{11}$ cm. There are only 24 students in the class. What is the overall average height (in cm) of all the students together in the class?

• A. $156\frac{3}{4}$
• B. 156
• C. 153
• D. 159
• E. $153\frac{3}{5}$

Answer 1

The correct option is B 156

Here, sum of the total height of 13 girls in the class $=13\times \frac{1880}{13}$
= 1880 cm
Sum of the total height of 11 boys in the class
$=11\times \frac{1864}{11}=1864cm$
$\therefore$ Overall average height $=\frac{1880+1864}{24}$
= 156 cm