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Question 3 - Figure it out - Page 149 - Chapter 6 Class 8 - We Distribute yet things Multiply (Ganita Prakash)
Last updated at January 13, 2026 by Teachoo
Class 8 (Ganita Prakash - 1, 2 & Old NCERT)
Chapter 6 Class 8 - We Distribute yet things Multiply (Ganita Prakash)
- Distributive Property
- Figure it out - Page 142, 143
- Fast Multiplications Using the Distributive Property
- Square of the Sum/Difference of Two Numbers
- Investigating Patterns
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Figure it out - Page 149
- Mind the Mistake, Mend the Mistake
- This Way or That Way, All Ways Lead to the Bay
- Area of Shaded Region
- Figure it out - Page 154-156
Transcript
Question 3 Find 4062, 722, 1452, 10972, and 1242 using the identities you have learnt so far.To find these, we use Sridharacharya’s identity a2 = (a + b) × (a – b) + b2 For 4062 We take a = 406, b = 6 4062 = (406 + 6) × (406 – 6) + 62 = 412 × 400 + 36 = 1,64,800 + 36 = 1,64,836 For 722 We take a = 72, b = 2 722 = (72 + 2) × (72 – 2) + 22 = 74 × 70 + 4 = 5,180 + 4 = 5,184 For 1452 We take a = 145, b = 5 1452 = (145 + 5) × (145 – 5) + 52 = 150 × 140 + 25 = 21,000 + 25 = 21,025 For 10972 We take a = 1097, b = 3 10972 = (1097 + 3) × (1097 – 3) + 32 = 1100 × 1094 + 9 = 12,03,400 + 9 = 12,03,409 For 1242 We take a = 124, b = 4 1242 = (124 + 4) × (124 – 4) + 42 = 128 × 120 + 16 = 15,360 + 16 = 15,376
