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Q. Find the number of ways of selecting 10 objects out of 30 objects of which 10 are alike and rest are different?
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2 Answers
62One better way than this Manoj could be that u select some of the different object...
which has to be less than half of 20 ie 10
so no of ways to select them is equal to half of total number of ways to select some of the 20 different objects..
So 220/2 = 219
You dont have to worry about the identical objects because whatever number you have selected (Say 6) you will select the remaining from identical ones( here 4)