Reduce Ratio 21:7

Here we will reduce the ratio 21:7 as much as possible. In other words, we will make the numbers 21 and 7 as low as they can be while still keeping the same ratio between the two numbers.

To do this we find the largest number that both 21 and 7 can be divided by. Then we divide both 21 and 7 by that number to get the new reduced ratio.

The largest number 21 and 7 can be divided by is 7. When we divide both numbers by 7, we get the new reduced ratio as follows:

3:1

To summarize, the ratio 21:7 reduced as much as possible is 3:1. You could also say that the ratio 21:7 equals 3:1.

Ratio Reducer
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