Answer:
13
Step-by-step explanation:
17-4=13 therefore 17-13=4
North American : South American : European
9 : 5 : 2
Multiply all by 10
90 : 50 : 20
The answer is 50 South American butterflies.
There are 6 apples and 2 oranges.
So the ratio of apples to oranges would be 6:2.
However this can be simplified, because these number have a common factor, which is 2. So you divide 2 by 2, and 6 by 2, and get 1 and 3. So the ratio of apples to oranges in simplified form is 1:3. Hope this explains it :)
