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1. I do not know how to solve the second question ?

Cans of lemon juice are supposed to contain 440 ml of juice. It is found that the actual volume of juice in a can is normally distributed with mean 445 ml and standard deviation 3.6 ml.
(i) Find the probability that a randomly chosen can contains less than 440 ml of juice. [3]

It is found that 94% of the cans contain between 445 − c ml and 445 + c ml of juice.
(ii) Find the value of c. [3]
2. (Original post by Sammysammy99)
I do not know how to solve the second question ?

Cans of lemon juice are supposed to contain 440 ml of juice. It is found that the actual volume of juice in a can is normally distributed with mean 445 ml and standard deviation 3.6 ml. (i) Find the probability that a randomly chosen can contains less than 440 ml of juice. [3]

It is found that 94% of the cans contain between 445 − c ml and 445 + c ml of juice. (ii) Find the value of c. [3]
Just like in one of your previous questions, make a sketch and indicate the info.

We have P(445-c < V < 445+c)=0.94.

This region is clearly symmetry about the mean. We can rewrite as:

2P(445 < V < 445 + c) = 0.94

Now try to obtain the form P(V < 445+c)=... to work with and deduce your c from there.
3. (Original post by RDKGames)
Just like in one of your previous questions, make a sketch and indicate the info.

We have P(445-c < V < 445+c)=0.94.

This region is clearly symmetry about the mean. We can rewrite as:

2P(445 < V < 445 + c) = 0.94

Now try to obtain the form P(V < 445+c)=... to work with and deduce your c from there.
Yes thank u I got it , after all this time

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