Aveterinarian needs to know an animals weight in kilograms. if 20 pounds is about 9 kilograms and a dog weighs 30 pounds, use a ratio table to find the dogs weight in kilograms

So, we know the weight for 20, but what we want to know is the weight for 30 pounds, that is 30/20=1.5 times more. 

So we need to multiply the number by 1.5 : 9*1.5=9+4.5=13.5

so the dog's weight in kilograms is around 13.5 kgs.

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