Answer:
a - Original length = 18; b - Original length = 12; c - Copy length = 15, ratio = 2/3
Explanation:
For part a, we know the ratio is 2/3. We also know the copy length is 27.
To change the denominator of the ratio to 27, we would multiply by 9; multiplying the top by 9, we have 2(9) = 18.
For part b, we know the ratio is 2/3. We also know the copy length is 18.
To change the denominator of the ratio to 18, we would multiply by 6; multiplying the top by 6, we have 2(6) = 12.
For part c, we only have one option left for the copy length; it must be 15.
This makes the ratio 10/15, which simplifies to 2/3.