JEE MATHEMATICS MCQ: COMBINATIONS

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The number of ways in which 20 letters

x_1, x_2, … x_{10}, y_1, y_2, …, y_{10}

be arranged in a line so that suffixes of the letters

x

and also those of

y

are respectively in ascending order of magnitude is

View answer and explanation

Correct option: D

184756

Option D (184756) is correct because it represents the number of ways to choose 10 positions for the x's (or y's) out of 20, with the order of the suffixes already determined.

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