To find the sum of the fractions \( \frac{920}{1} + \frac{720}{1} \), we simply add the two numbers together:
\[ 920 + 720 = 1640 \]
Thus, the sum in fraction form is:
\[ \frac{1640}{1} \]
Since \( \frac{1640}{1} \) is already in simplest form and can also be expressed just as \( 1640 \), our answer is:
\[ \boxed{1640} \]