# Math Help - normal distribution

1. ## normal distribution

can anyone help with this problem please:

the problem involves oranges n the masses in grams
the mass X grams of a particular variety of orange is normally distributed with mean 205g and standard deviation 25g

if the smallest 30% of oranges are graded 'small', how do you determine the maximum weight of an orange graded 'small'?

thanks, n apologies as that is all the information i have. i mainly looking for help how to determine it rather than the answer please.

2. Originally Posted by smiler
can anyone help with this problem please:

the problem involves oranges n the masses in grams
the mass X grams of a particular variety of orange is normally distributed with mean 205g and standard deviation 25g

if the smallest 30% of oranges are graded 'small', how do you determine the maximum weight of an orange graded 'small'?

thanks, n apologies as that is all the information i have. i mainly looking for help how to determine it rather than the answer please.
Solve for $a$: $\Pr(X \leq a) = 0.3$.