If the arithmetic means of two positive number a and b `(a gt b )` is – InterviewSolution

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1.	If the arithmetic means of two positive number a and b `(a gt b )` is twice their geometric mean, then find the ratio a: b
Answer» Correct Answer - `(2+ sqrt(3)):(2-sqrt(3))` Let A be the A.M. and G be the G.M. of a and b. Then the numbers a and b are roots of the equation `x^(2)-4Gx+G^(2)=0`b `[because a=2G]` `rArrx=(4Gpmsqrt(16G^(2)-4G^(2)))/2` `=(4Gpm2sqrt3G)/2=(2pmsqrt3)G` Hence, a:b=`(2+sqrt3):(2-sqrt3)`

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