Question

Assuming the balls to be identical except for difference in colours, the number of ways in which one or more balls can be selected from $10$ white, $9$ green and $7$ black balls is:

• A. $880$
• B. $629$
• C. $630$
• D. $879$

Answer 1

Answer: (D)

$879$

Number of ways of selecting one or more balls from 10 white, 9 green and 7 black balls
$=(10+1)(9+1)(7+1)-1$
$=879$