On the situation where taking the numbers 123456 how many numbers can u form using 3 digits with no numbers repeated is that a permutation or combination?

1 Answer
Jul 12, 2016

Answer:

Combination followed by permutation: #6C_3 X 3P_3=120#

Explanation:

Selection of 3 from 6 can be done in #6C_3=(6X5X4)/(1X2X3)=20# ways.

From each selection of 3 distinct digits, the digits can be

arranged, differently, in #3P_3 = 3X2X1= 6# ways.

So, the number of 3-git numbers formed = the product

20X6=120.