Engineering Board Exam Reviewer · Sequences and Series · medium
The geometric mean and arithmetic mean of two numbers are 8 and 17 respectively. Find the smaller (first) number.
- 2
- 8
- 16
- 34
Answer
A. 2
Solution
AM=a+b/2=17 gives a+b=34; GM=sqrt(ab)=8 gives ab=64. Solving t2-34t+64=0 gives t=2 or 32. The smaller number is 2.
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