The weighted average does not change. Doubling every weight scales both the numerator and denominator by 2, which cancel out completely, keeping the overall average strictly identical.
Class 9 Ganita Manjari Part 2 All Chapter Solutions
Class 9 Ganita Manjari Part 2 How Quantities Combine Understanding Data Question Answer
The weighted average remains completely unchanged. Algebraically, if each weight wᵢ is doubled to 2wᵢ, the new mean is Σ(2wᵢxᵢ)/Σ(2wᵢ). Factoring out the common factor of 2 gives [2Σ(wᵢxᵢ)]/[2Σwᵢ]. The factor 2 cancels from both numerator and denominator, leaving the original weighted mean formula intact. Scaling all weights by any constant preserves relative weights.
For more NCERT Solutions of Class 9 Maths Ganita Manjari Part 2 Chapter 10 How Quantities Combine Understanding Data Question Answer (2026-27)
https://www.tiwariacademy.com/ncert-solutions/class-9/maths/ganita-manjari-chapter-10/