Write the ratio of the first measurement to the second measurement.

Question

Diameter of care tire:40cm
Diameter of care tire:18mm

I'm not sure hoow to do this. May someone explain how to do this problem.

Answer 1

40 cm : 18 mm
= 40 cm : 1.8 cm
= 40 : 1.8
= 400 : 18
= 200 : 9