Question

The average of the middle two rational numbers if $\frac{4}{7},\frac{1}{3},\frac{2}{5},\frac{5}{9}$ are arranged in ascending order is:

• A. $\frac{86}{90}$
• B. $\frac{86}{45}$
• C. $\frac{43}{45}$
• D. $\frac{43}{90}$

Answer 1

The correct option is D $\frac{43}{90}$

$\frac{4}{7},\frac{1}{3},\frac{2}{5},\frac{5}{9}$
The above numbers in ascending order are
$\frac{1}{3}<\frac{2}{5}<\frac{5}{9}<\frac{4}{7}$
Middle two numbers are $\frac{2}{5}$ and $\frac{5}{9}$
$\therefore$ Average = $\frac{2/5+5/9}{2}=\frac{43}{90}$