JEE Previous Year Question
The sum of all the elements of the set { {1, 2,..., 100} : HCF (, 24) = 1} is_____.
Topic: JEE PYQ
Answer: 1633. Full step-by-step solution below.
Correct answer: 1633
Solution
(1633)HCF (, 24) = 1
Now, 24 = 22.3
is not the multiple of 2 or 3
Sum of values of
= S(U) -{S(multiple of 2) + S (multiple of 3) - S(multiple of 6)}
= (1 + 2 + 3 +......100) - (2 + 4 + 6.....+ 100) - (3 + 6 +.....99)+ (6+12+.....+96)
= 5050 - 2550 - 1683 + 816 = 1633 Ans.
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