Sir, how to solve those 'without replacement' type questions ? I generally get confuse in these types of problems. Please help me.

Asked by shivendra upadhyay | 18th Mar, 2013, 10:40: AM

Expert Answer:

Without replacement questions mean that you should use combinations in most case. It just means that if you have drawn out something from a box or a pack of cards, then the total number of cards will also reduce as well the number of specific card that you have drawn.
 
So, each time you draw something, there will be a change in the denominator because the total number of possibilities is changing. It is because of this reason, that we can use combinations for these questions. But, if that confuses you, you can just consider each event to be independent and write probability for all events taking place, keeping in mind that the total number will also decrease. 

Answered by  | 18th Mar, 2013, 05:14: PM

Queries asked on Sunday & after 7pm from Monday to Saturday will be answered after 12pm the next working day.