We set up a proportion to do this. There are 100 cm in 1 meter to we use this:
700 cm ( 1 m / 100 cm )
The cm's will cancel each other out since there is one in both the numerator and the denominator.
This leaves you with:
700 / 100 = 7.
The only units left when the centimeters cancel out is meters.
So there are 7 meters in 700 centimeters.