518:74=

To simplify the ratio 518:74, we can divide both sides by their greatest common divisor (GCD).

1. First, find the GCD of 518 and 74. The GCD is 37.

2. Now, divide both numbers by 37:

   • \( 518 \div 37 = 14 \)
   • \( 74 \div 37 = 2 \)

So, the ratio 518:74 simplifies to 14:2.

Further simplifying it gives us:

\( 14:2 = 7:1 \)

Thus, the simplified ratio is 7:1.