The table is
\\
| \
First Number x \ | \
\
Second Number \ | \
\
Product P \ | \
| \
10 \ | \
\
| \
\
| \
| \
20 \ | \
\
| \
\
| \
\
\
\
| \
First Number x \ | \
\
Second Number \ | \
\
Product P \ | \
| \
10 \ | \
\
| \
\
| \
| \
20 \ | \
\
| \
\
| \
| \
30 \ | \
\
| \
\
| \
| \
40 \ | \
\
| \
\
| \
| \
50 \ | \
\
| \
\
| \
| \
60 \ | \
\
| \
\
| \
| \
70 \ | \
\
| \
\
| \
| \
80 \ | \
\
| \
\
| \
| \
90 \ | \
\
| \
\
| \
| \
100 \ | \
\
| \
\
| \
The maximum is attained near x = 50 and 60.