Of a lot consisting 10 items 3 items are defective How many
     Of a lot consisting 10 items, 3 items are defective. How many ways can we choose different samples of 4 items from 10 items (order is not important)?  If we choose 4 items randomly from above 10 items, find the probability of getting  all 4 not defective.  at least 1 defective.  the first chosen is defective and the rest are not defective. 
  
  Solution

