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  1. Chapter 16 Class 8 Playing with Numbers
  2. Serial order wise


Ex 16.2, 1 If 21y5 is a multiple of 9, where y is a digit, what is the value of y? We know that, A Number is divisible by 9, if sum of digits is divisible by 9 21y5 Sum of digits = 2 + 1 + y + 5 = 8 + y Let us check different values of y & check if number is divisible by 9 Sum of digits = 8 + y

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Davneet Singh's photo - Teacher, Computer Engineer, Marketer
Davneet Singh
Davneet Singh is a graduate from Indian Institute of Technology, Kanpur. He has been teaching from the past 9 years. He provides courses for Maths and Science at Teachoo.