It's 12.5% Urban Puma.
To get one from the other, use 100.
For example, on the 1 in 8, divide 100 by 8 and you get the percentage, 12.5%.
If on the other hand you only have the percentage number, you divide 100 by that to get the "1 in" number. So if you have a 15% hill, divide 100 by 15 and that's 6.66, so roughly 1 in 7.
I'd estimate your bike can climb just about 1 in 10 (10%) without pedalling, and steeper than that depending on the rider. So 1 in 8 (12.5%) for a not very strong rider, 1 in 6 (17%) for a quite strong rider and 1 in 5 (20%) for a very fit rider.
As you can see, the rider is a very important factor, since these are electric assist bikes.
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