devavrat wrote:
How can all bulbs flash
The question says that every third bulb will flash. So If it starts from bulb no 1 then the third bulb will be bulb no 3
How can the third bulb be no 4
I hope to help you with this.
In general, every third means that the difference is 3
on a number line, every third number is 3,6,9,..... --> if the initial integer is 0
but if the initial integer is 1, then the sequence is 4,7,10,...
if you assume a sequence of 1,3,6,9,.. ---> it will be an incorrect sequence as the difference between the second and the first is not equal the difference between the third and the second.
if you assume a sequence of 1,3,5,... ---> it will be a sequence of every second number (as the difference is 2)
in other words: if the bulb no. 1 is not the first to flash, then the first one to flash will be bulb no. 3 followed by 6.
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