Question

Find the number of ways to listen to 4 different CDs from a selection of 10 CDs.

Answer 1

.. http://themediaeducation.com/education-questions-answers/find-number-ways-listen-different-from-selection-cWEtMjAxMjA4MTAwNzU2NDJBQTVMUU1n.html

Answer 2

There are 15 x 14 x 13 x 12 ways to listen to 4 different CDs out of 15.

Answer 3

i am wrong, @seiga is right

Answer 4

theres are the answer choices:


151,200

5040

2880

720

Answer 5

--151,200
5040
2880
720
--solution:
in this case the original answer should be
¹⁰C₄
= (10x9x8x7) / (1x2x3x4)
= 210

but from options it is clear that it is used ¹⁰P₄ = 10x9x8x7 = 5040 in the question paper

i m still sure that since it is not mentioned track wise or not. so it must be ¹⁰C₄ or 210 as answer.

hope it would be helpful