Question

The number of ways in which one or more balls can be selected out of $10$ white, $9$ green and $7$ black balls is

• A. $892$
• B. $881$
• C. $891$
• D. $879$

Answer 1

The correct option is D $879$

Required number of ways
$=(10+1)(9+1)(7+1)-1=880-1=879$