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Maths

How do i find out 75% of a cumulative frequency graph and answer if it is less or more than and prove that my answer is correct?
Original post by EstherFatunla
How do i find out 75% of a cumulative frequency graph and answer if it is less or more than and prove that my answer is correct?


Your question doesn't make much sense; if you provide a picture of the question it helps people to help you more easily.

Also I'd recommend posting this to the Maths section of study help rather than the GCSE section - you'll get a lot more attention over there,
Original post by TimGB
Your question doesn't make much sense; if you provide a picture of the question it helps people to help you more easily.

Also I'd recommend posting this to the Maths section of study help rather than the GCSE section - you'll get a lot more attention over there,


Okay thank you I will send a picture now
Original post by TimGB
Your question doesn't make much sense; if you provide a picture of the question it helps people to help you more easily.

Also I'd recommend posting this to the Maths section of study help rather than the GCSE section - you'll get a lot more attention over there,


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Original post by EstherFatunla
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Ah, ok. Draw a line up at weight = 3.4. Check where this crosses the graph. If the cumulative frequency at that point is less than 75, then she is wrong. In this case, the cumulative frequency at that point is about 57, suggesting that only 57% of the parcels have weight less than 3.4kg, not the 75% needed for her statement to be correct.

To find the correct answer, draw a line across at cf = 75. The weight at the point where it crosses is about 5.2kg, which suggests that 75% of parcels weigh less than 5.2kg. (Not actually needed for this question, but could be useful in future questions).
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Original post by TimGB
Ah, ok. Draw a line up at weight = 3.4. Check where this crosses the graph. If the cumulative frequency at that point is less than 75, then she is wrong. In this case, the cumulative frequency at that point is about 57, suggesting that only 57% of the parcels have weight less than 3.4kg, not the 75% needed for her statement to be correct.

To find the correct answer, draw a line across at cf = 75. The weight at the point where it crosses is about 5.2kg, which suggests that 75% of parcels weigh less than 5.2kg. (Not actually needed for this question, but could be useful in future questions).

Thank you so much but i have more questions to ask below:
20160417_105504.jpg
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There are 18 packets of sweets and 12 boxes of sweets in a carton.
The mean number of sweets in all the 30 packets and boxes is 14
The mean number of sweets in all the 18 packets is 10
Work out the mean number of sweets in the boxes
Original post by TimGB
Ah, ok. Draw a line up at weight = 3.4. Check where this crosses the graph. If the cumulative frequency at that point is less than 75, then she is wrong. In this case, the cumulative frequency at that point is about 57, suggesting that only 57% of the parcels have weight less than 3.4kg, not the 75% needed for her statement to be correct.

To find the correct answer, draw a line across at cf = 75. The weight at the point where it crosses is about 5.2kg, which suggests that 75% of parcels weigh less than 5.2kg. (Not actually needed for this question, but could be useful in future questions).

Thank you so much but i have more questions to ask below:
20160417_105504.jpg
Attachment not found
Attachment not found


There are 18 packets of sweets and 12 boxes of sweets in a carton.
The mean number of sweets in all the 30 packets and boxes is 14
The mean number of sweets in all the 18 packets is 10
Work out the mean number of sweets in the boxes
Original post by EstherFatunla
Thank you so much but i have more questions to ask below:
20160417_105504.jpg
Attachment not found
Attachment not found


There are 18 packets of sweets and 12 boxes of sweets in a carton.
The mean number of sweets in all the 30 packets and boxes is 14
The mean number of sweets in all the 18 packets is 10
Work out the mean number of sweets in the boxes


Answer for the first one:
Original post by EstherFatunla
Thank you so much but i have more questions to ask below:
20160417_105504.jpg
Attachment not found
Attachment not found


There are 18 packets of sweets and 12 boxes of sweets in a carton.
The mean number of sweets in all the 30 packets and boxes is 14
The mean number of sweets in all the 18 packets is 10
Work out the mean number of sweets in the boxes


Answer to the second one:
Original post by TimGB
Answer to the second one:


Thank you

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