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Thread ID: 108704 2010-04-08 04:44:00 Maths Problem bk T (215) PC World Chat
Post ID Timestamp Content User
874205 2010-04-08 04:44:00 Here is the question:

Three boys ran in race. Their total time was 24 min.

Bill ran 3 min faster than Peter.

Michael ran 3 times faster than Bill.

Find the race time of each boy.



My brain is not tuned to solve problems like this. Can some young, brainy people here help?
bk T (215)
874206 2010-04-08 04:59:00 "total time was 24 min"

Is this an aggregate of each boy's eleapsed time, or the time the slowest boy took?
johcar (6283)
874207 2010-04-08 05:01:00 Should be the total time taken for the 3 boys to complete the race bk T (215)
874208 2010-04-08 05:03:00 B+P+M=24
B+3=P
3M=B

Rearrange:

B+P+M=24
B-P=-3
3M-B=0

Now solve:

B=9
P=12
M=3

HTH :)
pcuser42 (130)
874209 2010-04-08 05:04:00 My brain is not tuned to solve problems like this. Can some young, brainy people here help?

Nahh, they're all out on the streets making heaps of noise. If this semi retired old bugger will do, I reckon Peter took 12 mins, Bill took 9 mins (3 less than Peter), and Michael ran the course in 3 minutes (1/3 the time of Bill). 12+9+3 = 12

I hope that's right! :blush:
WalOne (4202)
874210 2010-04-08 05:13:00 P=x (peters time is x)
B= P - 3 (bills time is peters less 3)
M= B - 3 (michael time is bills less 3)

this becomes....

P=x
B= x - 3
M= x - 3 - 3

or

P=x
B= X-3
M= x-6

so.....

X+(X-3)+(X-6) = 24

so...

3X - 9 = 24



x = 11
robsonde (120)
874211 2010-04-08 05:29:00 B+P+M=24
B+3=P
3M=B

Rearrange:

B+P+M=24
B-P=-3
3M-B=0

Now solve:

B=9
P=12
M=3

HTH :)

Your final answer look good but I still don't understand how you derive at those figures.

If you can elaborate a little further will nice:o
bk T (215)
874212 2010-04-08 05:38:00 Your final answer look good but I still don't understand how you derive at those figures.

If you can elaborate a little further will nice:o

The actual solving was done on my graphics calculator :D

The total time of all three people was 24 minutes, which makes B+P+M=24
Bill was three minutes faster than Peter, so Bill's time is three minutes less, therefore B=P-3 (B+3=P)
Michael was three times faster than Bill, so three times Michael's time is Bill's time: 3M=B

Then it's just rearranging into the form x+y+z=a so I can solve it on my calculator.

Confused? I'm not very good at explaining :p
pcuser42 (130)
874213 2010-04-08 05:40:00 P=x (peters time is x)
B= P - 3 (bills time is peters less 3)
M= B - 3 (michael time is bills less 3)

this becomes....

P=x
B= x - 3
M= x - 3 - 3

or

P=x
B= X-3
M= x-6

so.... .

X+(X-3)+(X-6) = 24

so...

3X - 9 = 24


x = 11

I have re-checked my math....

I still say the answer is:
B=8
P=11
M=5
robsonde (120)
874214 2010-04-08 05:50:00 The actual solving was done on my graphics calculator :D

The total time of all three people was 24 minutes, which makes B+P+M=24
Bill was three minutes faster than Peter, so Bill's time is three minutes less, therefore B=P-3 (B+3=P)
Michael was three times faster than Bill, so three times Michael's time is Bill's time: 3M=B

Then it's just rearranging into the form x+y+z=a so I can solve it on my calculator.

Confused? I'm not very good at explaining :p

I'm convinced that your answer is correct but still don't understand how you got it. It's OK if you can't explain it further, I'll try to crack my rusty brain and see how it goes.


I have re-checked my math....

I still say the answer is:
B=8
P=11
M=5

Are you sure your answer is correct?
M should be 3 times faster than B. your ans is not.
bk T (215)
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