Step-by-step explanation: Two ratios are equal if the fractions that represent the are equal.
So we first write the ratios 4 : 1 and 12 : 3 as the fractions 4/1 and 12/3.
Now, to determine whether the two fractions are equal,
we write each fraction in lowest terms.
Notice that 4/1 or 4 is already in lowest terms.
So let's move on.
12/3 can be simplified to 4.
So we have 4 = 4 which is true.
So that's how we know the ratios 4 : 1 and 12 : 3 are equal.