Answer: 21:9 and 42:18
Explanation:
14:6 at its most basic form is 7:3, so find anything that could be equal to this if a number is multiplied on both sides.
21:9 is our simplified ratio multiplied by 3 on both sides.
42:18 is our simplified ratio multiplied by 6 on both sides.
But, the final ratio doesn't work, because 7 and 3 respectively cannot multiply to 13 and 8 with the same value.