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# normal distribution watch

1. ive done the first 2 parts fo this question but i dunno where to start on the last 3, help much appreciated, thanks

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A brand of breakfast cereal is available in two sizes: the weights (in
grammes) of the edible contents, and packaging are both Normally distributed
with the following means and standard deviations:
Edible contents Packaging
Medium mean = 465, sd = 10 mean= 20, sd = 2
Large mean = 625, sd = 15 mean = 25, sd = 3
.
Find the probabilities that
1
• a randomly chosen Large box has a total weight exceeding 640 grammes,
• the total weight of the edible contents of 4 randomly chosen Large
boxes exceeds 2450 grammes.
• the edible contents of 4 randomly chosen Medium boxes weigh more
than the edible contents of 3 randomly chosen Large boxes.
• the total weight of 4 randomly chosen Medium boxes is more than
the total weight of 3 randomly chosen Large boxes.
• the total weight of 4 randomly chosen Medium boxes is more than
the total weight of 3 randomly chosen Large boxes when each box
also contains a small toy weighing exactly 50 grammes.
2. (Original post by eugenius 8)
• the edible contents of 4 randomly chosen Medium boxes weigh more
than the edible contents of 3 randomly chosen Large boxes.
For part 3, you're looking for

Or rearranging you're looking for:

So, the question is, what's the distribution of

Since you've done part 2, you can probably have a good stab at that.
3. What module is this?
4. (Original post by ghostwalker)
For part 3, you're looking for

Or rearranging you're looking for:

So, the question is, what's the distribution of

Since you've done part 2, you can probably have a good stab at that.
cheers, that really helped

(Original post by Hoody93)
What module is this?
its a statistical methods module for an accounting degree

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