If $a + 2b + 3c = 6$, then the greatest value of $abc^2$ is (where $a,b,c$ are positive real numbers)
$\frac{9}{8}$
$\frac{9}{16}$
$\frac{27}{8}$
$\frac{27}{16}$
If three unequal numbers $p,\;q,\;r$ are in $H.P.$ and their squares are in $A.P.$, then the ratio $p:q:r$ is
If $a$ be the arithmetic mean of $b$ and $c$ and ${G_1},\;{G_2}$ be the two geometric means between them, then $G_1^3 + G_2^3 = $
If $a,\,b,\,c,\,d$ are positive real numbers such that $a + b + c + d$ $ = 2,$ then $M = (a + b)(c + d)$ satisfies the relation
The sum of three consecutive terms in a geometric progression is $14$. If $1$ is added to the first and the second terms and $1$ is subtracted from the third, the resulting new terms are in arithmetic progression. Then the lowest of the original term is
For the two positive numbers $a , b$, if $a , b$ and $\frac{1}{18}$ are in a geometric progression, while $\frac{1}{ a }, 10$ and $\frac{1}{ b }$ are in an arithmetic progression, then, $16 a+12 b$ is equal to $.........$.