Question
Sum of three Natural numbers a, b and c is 10. How many ordered triplets (a, b, c) exist
Solution
Correct option is
(B)
Explanatory Answer
a + b + c = 10 , Let us place 10 sticks in a row
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now place two " + "
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This will become 4 + 5 + 1 , OR , a = 4 , b = 5 , c = 1
hence we hace 9 slots out of which 2 has to be selected for " + " s
now , number of ways = = 36
hence B is the correct option