Question

Assuming the balls to be identical expect 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. $879$
• B. $880$
• C. $629$
• D. $630$

Answer 1

The correct option is A $879$

Total no. of ways for selected one or more balls $=(10+1)(9+1)(7+1)-1$

$=11\times 10\times 8-1$

$=879$

Hence, the option $\left(A\right)$ is the correct answer.