If $a$ and $b$ are two different positive real numbers,then which of the following relations is true?

If $a, b, c$ are in $A.P.$ and $a, b, d$ are in $G.P.$,then $a, a - b, d - c$ will be in

Consider two positive numbers $a$ and $b$. If the arithmetic mean of $a$ and $b$ exceeds their geometric mean by $\frac{3}{2}$ and the geometric mean of $a$ and $b$ exceeds their harmonic mean by $\frac{6}{5}$,then the absolute value of $(a^2 - b^2)$ is equal to

If the arithmetic mean of two numbers is $A$ and the geometric mean is $G$,then the numbers are

The arithmetic mean and the geometric mean of two distinct $2$-digit numbers $x$ and $y$ are two integers,one of which can be obtained by reversing the digits of the other (in base $10$ representation). Then,$x+y$ equals

If the ratio of the Arithmetic Mean and Harmonic Mean of two positive real numbers $a$ and $b$ is $m:n$,then find the value of $a:b$.