Express the ratio in simplest form.

120cm to 45cm.

Both are divisible by 5.

24 to 9

These are divisible by 3.

30/41

18:27

To express the ratio 120cm to 45cm in simplest form, we need to find the greatest common divisor (GCD) of 120 and 45 and divide both numbers by it.

First, let's find the GCD of 120 and 45. We can use the prime factorization method to find the GCD.

Prime factorization of 120: 2 * 2 * 2 * 3 * 5 = 2^3 * 3 * 5
Prime factorization of 45: 3 * 3 * 5 = 3^2 * 5

Now, we look for common prime factors and multiply them together to find the GCD: 3 * 5 = 15

Next, we divide both numbers by the GCD:

120 ÷ 15 = 8
45 ÷ 15 = 3

Now, the ratio 120cm to 45cm in simplest form is 8:3.