ratios can be written as fractions...so 4:3 is 4/3
an equivalent ratio would be the same as an equivalent fraction
to find equivalent fractions (ratios), multiply the numerator and denominator by the same number...
4/3 * 2/2 = 8/6.....so 8:6 is an equivalent ratio
4/3 * 3/3 = 12/9...so 12:9 is an equivalent ratio
4/3 * 4/4 = 16/12...so 16:12 is an equivalent ratio
etc...