JEE Main 2025 — Permutation Combination Question with Solution
JEE Main 2025 (4 Apr Shift 2)
Question
Let m and be two 2-digit numbers. Then the total numbers of pairs , such that , is ________
Enter your answer
Show full solutionCorrect answer: 64
Correct answer
64
Step-by-step explanation
Let
where are co-prime numbers also since are 2 digit nos, so
i.e.
( a is integer)
Now
are co-prime
if
64 ordered pairs
where are co-prime numbers also since are 2 digit nos, so
i.e.
( a is integer)
Now
are co-prime
if
64 ordered pairs
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This is a previous-year question from JEE Main 2025, covering the Permutation Combination chapter of Mathematics. PrepSharp catalogues every PYQ from JEE Main with a verified answer key and step-by-step solution prepared by IIT alumni — so you can search by chapter, topic or year and revise efficiently.