9709 P61 - Nov 2012 - Q3
3255
Lengths of rolls of parcel tape have a normal distribution with mean 75 m, and 15% of the rolls have lengths less than 73 m.
- Find the standard deviation of the lengths.
Alison buys 8 rolls of parcel tape.
- Find the probability that fewer than 3 of these rolls have lengths more than 77 m.
