Common Admission Test
As a general category student apart from a strong profile you need to have atleast 95+ percentile even to get a call from any ultra new IIM. So, unfortunately, your son will not get a call from any IIM.
With 87.1 percentile as a general category student, for your son,
Try joining a coaching class.
Devote 8-12 hours per day.
Prepare chapterwise for each subject and give sectional mocks.
Give 50% time for English and rest 50% for other subjects.
Develop a reading habit and increase your reading speed atleast upto 600wpm.
For every Subject try covering important chapters first
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