ration? You deserve better from your teacher.
The ratio of auditorium to theater seats is
1200:320
That's a perfectly valid answer and we could stop here if we weren't asked for lowest terms. Here I can see that 12 and 32 have a common factor of 4 and both these end in zero so 40 is a common factor:
1200:320 = 30:8
We can keep reducing by another factor of 2,
1200:320 = 30:8 = 15:4
There's our 15/4, which we get when we write the ratio as a fraction.
Answer: 15/4
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This question implies a ratio is just a fraction, which it isn't. Let's quickly note the differences.
A ratio can have zero on either side; 1:0 is a perfectly valid ratio but 1/0 is not a valid fraction. A ratio can't be all zeros -- that's not allowed.
A ratio can have more than two numbers. 3:4:5 is a common ratio that gives rise to a right triangle.
Like fractions, ratios can be reduced: For λ≠0,
λa : λb : λc = a:b:c