Mathematics - Permutation & Combination Question with Solution | TestHub

MathematicsPermutation & CombinationnPr & nCrHard2 minPYQ_2006

MathematicsHardsingle choice

If $r, s, t$ are prime numbers and $p, q$ are the positive integers such that LCM of $p, q$ is $r^{2} s^{4} t^{2}$ , then the number of ordered pairs $(p, q)$ is

Options:

Answer:

Solution:

Since, $r, s, t$ are prime numbers. $∴$ Selection of $p$ and $q$ are as under
$∴$ Total number of ways to select $s = 9$ . Similarly, the number of ways to select $t = 5$ . $∴$ Total number of ways $= 5 \times 9 \times 5 = 225$ .

Stream:JEE_ADVSubject:MathematicsTopic:Permutation & CombinationSubtopic:nPr & nCr

⏱ 2mℹ️ Source: PYQ_2006

Doubts & Discussion

Loading discussions...