Question
Of 10 computer chips, 4 are defective. What is
the probability of selecting 3 without replacement, only one of which is defective?Solution
There are only 3 ways in which just one can be defective:
-  only the first is defective 
-  only the second is defective 
-  only the third is defective 
According to the rule of multiplication, 
- Calculate the volume of a sphere whose diameter measures 21 cm. (Take π = 22/7) 
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