Engineering Board Exam Reviewer · Sequences and Series · medium
The arithmetic mean of 6 numbers is 17. If two numbers are added, the new set of numbers will have an arithmetic mean of 21. What are the two numbers if their difference is 4?
- 30 & 34
- 32 & 36
- 31 & 35
- 33 & 38
Answer
C. 31 & 35
Solution
Original sum of 6 numbers = 6(17)=102. New sum of 8 numbers = 8(21)=168, so the two added numbers sum to 66 and differ by 4. Solving gives 35 and 31.
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