- 1). Divide the ratio. The first number is the denominator and the second number is the numerator. For example, 1/3 = 0.3333333333....
- 2). Determine how precise you want the number by figuring where you want to round the number. In the example, assume you want it to the fifth decimal place.
- 3). Round the number to your decimal place. If the next number is five or more, then round up, if the number is less than five then round down. In the example, you would have 0.33333. You round down because three is less than five.
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