on a frequency table about weight of crisps:
frequency= 15,10,20,40,10
weight in grams=14-16,16-18,18-20,20-22,22-24
the mean is 19
95% of the product contain at least how much crisps?
ok mmm id double check this but from the information you give me id think your best bet is to form a normal distribution
you are told mean =19
you can work out the sample variance and standard deviation from the info your told using the formula.
this would be my first approach.