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Question 1 - Figure it out - Page 143, 144 - Chapter 6 Class 7 - Number Play - Ganita Prakash
Last updated at October 17, 2025 by Teachoo
Class 7 (Ganita Prakash 1, 2 & old NCERT)
Chapter 6 Class 7 - Number Play - Ganita Prakash
- Numbers can Tell us Things, Supercells
- Parity
- Figure it out - Page 131
- Small Squares in Grids (Parity in Multiplication)
- Parity of Expressions
- Some Explorations in Grids
- Magic Square
- Figure it out - Page 136
- Generalising 3 × 3 Magic Square
- First ever 4 × 4 Magic Square
- Magic Squares in History and Culture
- Virahāṅka Fibonacci Numbers
- Digits in Disguise
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Figure it out - Page 143, 144
Transcript
Question 1 A light bulb is ON. Dorjee toggles its switch 77 times. Will the bulb be on or off? Why? The state of the bulb depends on the parity (odd or even) of the number of times the switch is toggled. It starts ON After 1 toggle (odd), it's OFF After 2 toggles (even), it's ON After 3 toggles (odd), it's OFF The bulb is OFF after an odd number of toggles. Since Dorjee toggles the switch 77 times, which is an odd number, the bulb will be in the OFF state
