There are 15 stamps from which two stamps will be selected. Tom has three stamps which are same as five of the ten stamps to be selected. What is the probability that two stamps selected will not be one of the stamps that Tom has?
A. 3/7
B. 8/15
C. 6/17
D. 5/18
E. 7/15
* A solution will be posted in two days.
There are 15 stamps from which two stamps will be selected.
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- Max@Math Revolution
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The number of stamps that Tom has is 5 and the number of stamps that Tom does not have is 10. Hence, we can calculate 10C2/15C2=[(10)(9)/2!]=[(15)(14)/2!]=3/7. Thus, the correct answer choice is A.
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