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# S2 help! Watch

1. So I'm really stuck on part of an S2 question on normal distributions. The question is:
The length of a component may be modelled as a normal distribution with a standard deviation 3cm. 15% of the components are longer than 16cm. Calculate the mean length and percentage longer than 12cm.

I've found the mean, but when I tried to find the percentage longer than 12cm I got a weird answer that isn't right but I'm not sure what to do!
Any help would be awesome!
2. (Original post by phoebeg76)
So I'm really stuck on part of an S2 question on normal distributions. The question is:
The length of a component may be modelled as a normal distribution with a standard deviation 3cm. 15% of the components are longer than 16cm. Calculate the mean length and percentage longer than 12cm.

I've found the mean, but when I tried to find the percentage longer than 12cm I got a weird answer that isn't right but I'm not sure what to do!
Any help would be awesome!
What does this mean? Did the answer have a beard or something...

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Updated: January 11, 2015
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