72% of 25 students are good in mathematics. How many are not good in mathematics?

Total number of students = 25
Number of good students in mathematics = 72% of 25 = 72/100×25=18
Number of students not good in mathematics = 25 – 18 = 7
Hence percentage of students not good in mathematics = 7/25×100=28%

Class 8 Maths Chapter 8 Exercise 8.3 Solution in Video

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