- Messages
- 2
- Reaction score
- 1
- Points
- 3
this is w12 paper 61. i did the first part. dont understand the second one. please help. i need help . i am frustrated. thanks.
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.
(i) Find the standard deviation of the lengths. [3]
Alison buys 8 rolls of parcel tape.
(ii) Find the probability that fewer than 3 of these rolls have lengths more than 77 m
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.
(i) Find the standard deviation of the lengths. [3]
Alison buys 8 rolls of parcel tape.
(ii) Find the probability that fewer than 3 of these rolls have lengths more than 77 m