Originally Posted by

**Soroban** Hello, thereddevils!

Is there a typo?

The numbers don't seem to be reasonable.

Let $\displaystyle x$ = $\displaystyle P$'s age in 1988.

In 1988, we have:

$\displaystyle \begin{array}{c|c|c|c|}

& P & Q & R \\ \hline \hline

1988 & x & 3x & 3x-25 \\ \hline\end{array}$

In 1985 (7 years later), we have:

$\displaystyle \begin{array}{c|c|c|c|c|}

& P & Q & R & S \\ \hline \hline

1995 & x+7 & 3x+7 & 3x-18 & \frac{1}{4}(x+7) \\ \hline \end{array}$

In 2004 (9 years later), we have:

$\displaystyle \begin{array}{c|c|c|c|c|}

& P & Q & R & S \\ \hline \hline

2004 & x+16 & 3x+16 & 3x - 9 & \frac{1}{4}(x+7)+9 \\ \hline \end{array}$

At this time, $\displaystyle S$ is 21: .$\displaystyle \tfrac{1}{4}(x+7) + 9 \:=\:21 $

. . $\displaystyle \tfrac{1}{4}(x+7) \:=\:12 \quad\Rightarrow\quad x + 7 \:=\:48 \quad\Rightarrow\quad x \:=\:41$

Therefore, in 1988, $\displaystyle P$ was 41 years old . . . and $\displaystyle {\color{blue}Q}$ *was 123** ??*