Respuesta :

you can use cross products to see whether two ratios are equal and form a proportion. 
ratios can also be written as fractions. So when the ratios are in fraction form, they are proportionate if they are equivalent fractions.

for example....lets say if ur 2 ratios are 2:4 and 8:16....put them in fraction form.....2/4 and 8/16....
2/4 reduces to 1/2
8/16 reduces to 1/2
so these 2 ratios are proportionate because they are equivalent fractions

another example.....u have 2 ratios which are 3:5 and 6:12
3/5 and 6/12
3/5...does not reduce
6/12 = 1/2
these are not proportionate because they are not equivalent fractions