Question 9 - Figure it out - Page 154-156 - Chapter 6 Class 8 - We Distribute yet things Multiply (Ganita Prakash)

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Question 9 Which is larger? Find out without fully computing the product. (i) 14 × 26 or 16 × 24Now, 14 × 26 = (20 – 6) × (20 + 6) Using (a – b) (a + b) = a2 – b2 = 202 – 62 And, 16 × 24 = (20 – 4) × (20 + 4) Using (a – b) (a + b) = a2 – b2 = 202 – 42 Since in 16 × 24 we are subtracting smaller number (42 instead of 62), Thus, 16 × 24 is larger Question 9 Which is larger? Find out without fully computing the product. (ii) 25 × 75 or 26 × 74Now, 25 × 75 = (50 – 25) × (50 + 25) Using (a – b) (a + b) = a2 – b2 = 502 – 252 And, 26 × 74 = (50 – 24) × (50 + 24) Using (a – b) (a + b) = a2 – b2 = 502 – 242 Since in 26 × 74 we are subtracting smaller number (242 instead of 252), Thus, 26 × 74 is larger