Question 1 - Page 128 - Shortcut for Divisibility by 11 - Chapter 5 Class 8 - Number Play (Ganita Prakash)

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Question 1 - Page 128 Using this shortcut, find out whether the following numbers are divisible by 11. Further, find the remainder if the number is not divisible by 11. (ii) 841 841 Sum of digits at Odd Places = 8 + 1 = 9 Sum of digits at Even Places = 4 Difference = 9 − 4 = 5 Since 5 is not divisible by 11 ∴ 841 is not divisible by 11 Question 1 - Page 128 Using this shortcut, find out whether the following numbers are divisible by 11. Further, find the remainder if the number is not divisible by 11. (iii) 481Question 1 - Page 128 Using this shortcut, find out whether the following numbers are divisible by 11. Further, find the remainder if the number is not divisible by 11. (iii) 481 481 Sum of digits at Odd Places = 4 + 1 = 5 Sum of digits at Even Places = 8 Difference = 5 − 8 = –3 Since –3 is not divisible by 11 ∴ 481 is not divisible by 11 Question 1 - Page 128 Using this shortcut, find out whether the following numbers are divisible by 11. Further, find the remainder if the number is not divisible by 11. (iv) 5529 5529 Sum of digits at Odd Places = 5 + 9 = 13 Sum of digits at Even Places = 5 + 2 = 7 Difference = 13 − 7 = 6 Since 6 is not divisible by 11 ∴ 5529 is not divisible by 11 Question 1 - Page 128 Using this shortcut, find out whether the following numbers are divisible by 11. Further, find the remainder if the number is not divisible by 11. (v) 90904 90904 Sum of digits at Odd Places = 9 + 9 + 4 = 22 Sum of digits at Even Places = 0 + 0 = 0 Difference = 22 − 0 = 22 Since 22 is not divisible by 11 ∴ 90904 is not divisible by 11 Question 1 - Page 128 Using this shortcut, find out whether the following numbers are divisible by 11. Further, find the remainder if the number is not divisible by 11. (vi) 857076 857076 Sum of digits at Odd Places = 5 + 0 + 6 = 11 Sum of digits at Even Places = 8 + 7 + 7 = 22 Difference = 11 − 22 = –11 We can ignore the negative sign Since –11 is divisible by 11 ∴ 857076 is divisible by 11