Which of the following is the largest fraction ? 6/7, 5/6, 7/8, 4/5

Answer: Option D

$$\begin{array}{rl}& \frac{6}{7},\frac{5}{6},\frac{7}{8},\frac{4}{5}\\ & \frac{6}{7}=0.85,\\ & \frac{5}{6}=0.83,\\ & \frac{7}{8}=0.87,\\ & \frac{4}{5}=0.80\\ & \frac{7}{8}\text{is}\text{largest}\end{array}$$

Explanation :
When the fractions are given in this order when the difference between the numerator and denominator is same so largest fraction will be largest numerator fraction and the smallest will be smallest numerator fraction.
Note: - Fraction should be in the order where denominator will be larger than numerator.
In this question : largest is $$\frac{7}{8}$$and smallest is $$\frac{4}{5}$$