Can someone plz explain ratio to me​

A ratio shows how much of one thing there is compared to another. Ratios are usually written in the form a:b. If you are making orange squash and you mix one part orange to four parts water, then the ratio of orange to water will be 1:4 (1 to 4). The order in which a ratio is stated is important.

it is 10.6 according to my calculations

he answer is x=1x3 because x=1 to x=3