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Ex 3.2, 3
Last updated at May 7, 2026 by Teachoo
Class 9
Chapter 3 Class 9 - The World of Numbers (Ganita Manjari I)
- The Human Need to Count
- Exercise Set 3.1
- The Revolution of Śhūnya
- Integers
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Exercise Set 3.2
Transcript
Ex 3.2, 3 (i) Calculate the following using Brahmagupta’s laws: (i) (–12) × 5 Since Positive × Negative = Negative We can write –12 × 5 = –(12 × 5) = –60 Ex 3.2, 3 (ii) Calculate the following using Brahmagupta’s laws: (ii) (–8) × (–7) Since Negative × Negative = Positive We can write (–8) × (–7) = 8 × 7 = 56 Ex 3.2, 3 (iii) Calculate the following using Brahmagupta’s laws: (iii) 0 – (–14) Now, Subtracting a negative is same as adding a positive (Removing a debt is same as being richer) So, we can write 0 – (–14) = 0 + 14 = 14 Ex 3.2, 3 (iv) Calculate the following using Brahmagupta’s laws: (iv) (–20) ÷ 4 Now, A negative divided by a positive is a negative (A big debt divided over several months is a small debt, but still a debt) So, we can write (–20) ÷ 4 = (−20)/4 = –5
