Question 1 - Figure it out - Page 145-147 - Chapter 6 Class 8 - Algebra Play (Ganita Prakash II)

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Question 1 In the trick given above, what is the quotient when you divide by 9? Is there a relationship between the two numbers and the quotient?Let’s remember our trick Choose a 2-digit number(with different digits): Shubham secretly picks 47. Reverse the digits: 47 becomes 74 . Find the difference: Subtract the smaller number from the larger number: 74−47=27 Divide the result by 9: 27/9=3. From algebra, we found out that (10b + a) – (10a – b) = 10b – b – 10a + a = 9b – 9a = 9 (b – a) Dividing by 9 (9(𝑏 − 𝑎))/9 = (b – a) Basically, this is the difference between two digits we picked Example: For 47, our quotient comes out to be 7 – 4 = 3