1.  The percentage of number of students getting at least 60% marks in Chemistry over those getting at least 40% marks in aggregate, is approximately?

A. 21%
B. 27%
C. 29%
D. 31%

Answer: Option C

Explanation:

Number of students getting at least 60% marks in Chemistry

    = Number of students getting 30 and above marks in Chemistry

    = 21.

Number of students getting at least 40% marks in aggregate

    = Number of students getting 20 and above marks in aggregate

    = 73.

Required percentage
= ( 21 x 100 ) %
73
= 28.77%
~= 29%.