Final answer:
An equivalent ratio to 5:9 can be found by multiplying or dividing both numbers in the original ratio by the same number. An example would be multiplying both by 2, giving the equivalent ratio of 10:18.
Step-by-step explanation:
In the subject of Mathematics, specifically ratios, if Jakob needs to find an equivalent ratio to 5:9, he can use the multiplication or division method to keep the ratio constant. For instance, if you multiply both sides by the same number. Let's consider 2 for an example. This would make the ratio 5*2 : 9*2 = 10 : 18, which is equivalent but larger. Remember, you can also divide if you need a smaller equivalent ratio. As long as the same operation (whether multiplication or division) is applied to both numbers in the ratio, the ratios will remain equivalent.
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