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November 14th, 2018, 12:29 PM   #1
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Help on these, found it to be very tough...

1. The ratio of girls to boys is 5:6. On a rainy day, 1/6 of girls and 1/4 of boys were absent. If the total number of pupils present was 390, how many of the pupils were boys?
2. Two cars X and Y start at the same point and travel toward point P which is 150km away.
If the average speed of Y is 60km/h and X arrives at P 25 minutes earlier, what is the average speed of X?
3. A & B can do a piece of work in 15 days. They both started, but after 6 days B gets ill and A takes 30 more days to finish the job himself. How long would each take working alone?

Last edited by skipjack; November 15th, 2018 at 03:53 AM.
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November 14th, 2018, 01:28 PM   #2
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Would be easier to "help" if you posted only ONE problem per thread.
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November 14th, 2018, 01:38 PM   #3
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Sorry as I need the solution to those urgently
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November 14th, 2018, 01:45 PM   #4
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Quote:
Originally Posted by Denis View Post
Would be easier to "help" if you posted only ONE problem per thread.
And if you provided your working...
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November 14th, 2018, 03:00 PM   #5
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What always baffles me is that more time is spent trying to obtain a "quick answer" than actually just showing some scratch work/your thoughts on the problem..

Do you understand what I mean by this Harmeed?
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November 14th, 2018, 03:52 PM   #6
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Quote:
Originally Posted by Harmeed View Post
Sorry as I need the solution to those urgently
Apologies...tomorrow soon enough?
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November 14th, 2018, 04:21 PM   #7
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Quote:
Originally Posted by Harmeed View Post
1. The ratio of girls to boys is 5:6. On a rainy day, 1/6 of girls and 1/4 of boys were absent. If the total number of pupils present was 390, how many of the pupils were boys?
Hint:
b = boys, g = girls
g/b = 5/6 : b = 6g/5

5g/6 + 3b/4 = 390

Last edited by skipjack; November 15th, 2018 at 03:54 AM.
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November 14th, 2018, 08:19 PM   #8
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Thanks for the hint... Was of the rest?
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November 14th, 2018, 09:13 PM   #9
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I obtained 240
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November 15th, 2018, 03:55 AM   #10
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Are you sure the numbers of pupils are correct?

For every 30 girls and 36 boys, 25 girls and 27 boys attended, so the number of pupils who attended must be a multiple of 52, such as 364 or 416, not 390.

Last edited by skipjack; November 15th, 2018 at 01:50 PM.
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