Answer:
6:9:15
Explanation:
multiply each number in the first ratio by three. They multiplied 3 times three to get 9, so you have to do that to each number to make it a ratio.
A ratio is like an equivalent fraction. It all has to be proportionate to the other fraction.
Examples:
4:3 is equal to 8:6
16:6 is equal to 32:12