Option D. 96 is the correct answer.
Explanation:
Let the higher grade be = x
Let the lower grade be = y
As given, The difference of the two grades is 16
[tex]x-y=16[/tex] or [tex]x=16+y[/tex] .... (1)
The sum of one-eighth of the higher grade and one-half of the lower grade is 52.
[tex]\frac{1x}{8}+\frac{1y}{2}=52[/tex] ... (2)
Putting the value of x=16+y in equation (2)
[tex]\frac{16+y}{8}+\frac{y}{2}=52[/tex]
[tex]\frac{16+y+4y}{8}=52[/tex]
[tex]\frac{16+5y}{8}=52[/tex]
[tex]16+5y=416[/tex]
[tex]5y=400[/tex]
[tex]y=80[/tex]
As x=16+y
x=16+80 = 96
Hence, higher grade is 96.