Explanation:
For y/x to be as high as possible, y must have the highest possible value and x must have the lowest possible value. (12 and 6)
Hence, y/x < 12/6, which is 2.
For y/x to be as low as possible, y must have the lowest possible value and x must have the highest possible value (10 and 7)
Hence, y/x > 10/7.
Combining the 2 inequalities, we have 10/7 < y/x < 2.