Three ratios equivalent to 1 to 3.

Ratios are really fractions, so 1 to 3 is really

1/3

it works the same way equivalent fractions do: multiply both numbers (numerator and denominator) by the same number, and the ratio will stay the same. So if we multiply it by 2, we get:

2 to 6

3,

3 to 9

10,

10 to 30

100,

100 to 300