# Thread: Normal Distribution Question . Find the probability that none of...

1. ## Normal Distribution Question . Find the probability that none of...

A supermarket sells 2 types of berries - blue berries and black berries

Each type of berries comes in different sized packing and any randomly selected packet is normally distributed with mean and standard deviation as shown below:

Blue berries : mean(kg) = 1.2 standard deviation(kg) = 0.2
Black berries: mean(kg) = 1.1 standard deviation(kg) = 0.1

Andre picks one packet of blue berries and one packet of black berries.

Find the probability that none of the two packets picked by Andre weighs less than 1.2kg.

Thank you! will appreciate any help at all

2. ## Re: Normal Distribution Question . Find the probability that none of...

Originally Posted by pumbaa213
A supermarket sells 2 types of berries - blue berries and black berries

Each type of berries comes in different sized packing and any randomly selected packet is normally distributed with mean and standard deviation as shown below:

Blue berries : mean(kg) = 1.2 standard deviation(kg) = 0.2
Black berries: mean(kg) = 1.1 standard deviation(kg) = 0.1

Andre picks one packet of blue berries and one packet of black berries.

Find the probability that none of the two packets picked by Andre weighs less than 1.2kg.

Thank you! will appreciate any help at all
$Pr[$neither packet $<1.2$kg$]=1-Pr[$both packets $<1.2$kg$]$

Packets are statistically independent so

$Pr[$both packets $< 1.2$kg$] = Pr[$blue berries $< 1.2$kg$]\cdot Pr[$black berries $<1.2$kg$]$

can you figure out those individual probabilities and complete the problem?