Engineering Board Exam Reviewer · Sequences and Series · medium
Insert 4 arithmetic means between 5 and 30. What is the third mean?
- 15
- 25
- 17.5
- 20
Answer
D. 20
Solution
The sequence has 6 terms with a1=5 and a6=30, so d=30-5/5=5. The means are 10,15,20,25, and the third is 20.
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