CA Foundation · Quantitative Aptitude · Sets, Relations and Functions, Limits and Continuity
A set is given by A = {x : x is an integer and -2 < x ≤ 3}. How many elements does A have, and what is the sum of its elements?
A = {-1, 0, 1, 2, 3}, since -2 is excluded and 3 is included. It has 5 elements and their sum is 5. Counting -2 wrongly would give six elements with sum 3.
- A5 elements, sum 5Correct
- B5 elements, sum 6
- C6 elements, sum 5
- D6 elements, sum 3
Explanation
Integers greater than -2 and up to 3 are -1, 0, 1, 2, 3. That is 5 elements. Sum = -1+0+1+2+3 = 5. Including -2 would give 6 elements and sum 3, which is wrong because -2 < x is strict.
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