Question 1 - Figure it out - Page 143, 144 - Chapter 6 Class 7 - Number Play - Ganita Prakash

Last updated at August 14, 2026 by

A light bulb is ON. Dorjee toggles its switch 77 times. Will the bulb - Figure it out - Page 143, 144

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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

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