Answer is the ratio 11:13
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Step-by-step explanation:
Start by writing the ratio 198:234 in that exact order
Then factor each piece
198 = 18*11
234 = 18*13
We see that 18 is the GCF of 198 and 234. Divide both parts by the GCF to end up with these results
198/18 = 11
234/18 = 13
Therefore, the ratio 198:234 fully reduces to 11:13