CSAT 2023

Q. If today is Sunday, then which day is it exactly on 10^10 th day?

(a) Wednesday
(b) Thursday
(c) Friday
(d) Saturday
Correct Answer: (a) Wednesday (Official Answer)

Question from UPSC Prelims 2023 CSAT

Explanation : 

Calculating the 10^10 day starting from Sunday

The solution is as follows:

– We know that there are 7 days in a week, so we can divide 10^10 by 7 to get the number of complete weeks and the remainder.
– 10^10 / 7 = 1428571428 weeks and 4 days.

The remainder 4 is what we’re interested in. It tells us that on 10^10 days, it will be the 4th day of the week, counting from today.

If today is Sunday, then the 4th day from today (inclusive) is Wednesday.
(Sunday – Day 1, Monday – Day 2, Wednesday – Day 3, Thursday –  Day 4)

Therefore, the correct answer is (a) Wednesday.

Note: We have updated the answer & solution. Thursday would have been answer if question had asked after 10^10 days.

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