NDA2010MathematicsSequences and SeriesActual
If the AM and HM of two numbers are 27 and 12 respectively, then what is their GM equal to?
Options
- A12
- B18
- C24
- D27
Correct answer
A. 12
Step-by-step solution
Let the two numbers be a and b . So, a+b 2 =27 , and aligned & 1 a + 1 b 2 =12 b+a 2 a b =12 & a b= 27 12 = 9 4 & G.M. = a b = 3 2 aligned