1. R
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    01 Jul '20 15:311 edit
    Bob, John and Josh are running a 1 km race. Each competitor runs at a constant rate.

    After Bob has run 1/4 km, Bob is ahead of John by 25 meters.
    After John has run 1/2 km, John is ahead of Josh by 20 meters.

    When Bob finishes the race, by how much distance does he beat Josh?
  2. Subscribervenda
    Dave
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    01 Jul '20 18:34
    @joe-shmo said
    Bob, John and Josh are running a 1 km race. Each competitor runs at a constant rate.

    After Bob has run 1/4 km, Bob is ahead of John by 25 meters.
    After John has run 1/2 km, John is ahead of Josh by 20 meters.

    When Bob finishes the race, by how much distance does he beat Josh?
    Bob beats John by 100 mtrs
    John beats Josh by 40mtrs.
    So Bob beats Josh by 140 mtrs
  3. R
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    01 Jul '20 18:361 edit
    @venda said
    Bob beats John by 100 mtrs
    John beats Josh by 40mtrs.
    So Bob beats Josh by 140 mtrs
    Sorry, Try again.
  4. Subscribervenda
    Dave
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    01 Jul '20 19:26
    @joe-shmo said
    Sorry, Try again.
    Half way thro' the race:-
    Bob = 500mtrs
    John = 475mtrs
    Josh = 455 mtrs
    500*2 = 1000
    475*2 =950
    455*2 = 910
    Therfore Bob beats Josh by 90mtrs
  5. R
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    01 Jul '20 19:311 edit
    @venda said
    Half way thro' the race:-
    Bob = 500mtrs
    John = 475mtrs
    Josh = 455 mtrs
    500*2 = 1000
    475*2 =950
    455*2 = 910
    Therfore Bob beats Josh by 90mtrs
    unfortunately...your getting further away.
  6. Subscribervenda
    Dave
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    01 Jul '20 19:50
    @joe-shmo said
    unfortunately...your getting further away.
    I wrote it down this time.
    Is it 40?
  7. R
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    01 Jul '20 19:57
    @venda said
    I wrote it down this time.
    Is it 40?
    Nope
  8. Subscribervenda
    Dave
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    01 Jul '20 20:01
    @joe-shmo said
    Nope
    Oh well.
    I used to do these things all the time.
    I'm obviously a little out of practice(and a lot older)
    I'll let someone else have a go.
    Thanks anyway
  9. R
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    01 Jul '20 20:101 edit
    @venda said
    Oh well.
    I used to do these things all the time.
    I'm obviously a little out of practice(and a lot older)
    I'll let someone else have a go.
    Thanks anyway
    Thanks for trying! If you want to give it another go later on, feel free to do so. If you don't figure it out, you'll kick yourself when you see it.
  10. Subscribervenda
    Dave
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    01 Jul '20 20:24
    @joe-shmo said
    Thanks for trying! If you want to give it another go later on, feel free to do so. If you don't figure it out, you'll kick yourself when you see it.
    Don't do kicking anymore.
    Got an arthritic hip!!
    From your tone I think there might be a catch in the wording.
    However once more:-
    After 250 mtrs run by Bob, John has run 225 mtrs Josh has run 215 mtrs
    This means Bob is 45 mtrs in front of Josh
    4*250 =1Km
    4*45 = 180 mtrs behind.
    180mtrs -final answer!! and I've used all my lifelines!!
  11. R
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    01 Jul '20 20:29
    @venda said
    Don't do kicking anymore.
    Got an arthritic hip!!
    From your tone I think there might be a catch in the wording.
    However once more:-
    After 250 mtrs run by Bob, John has run 225 mtrs Josh has run 215 mtrs
    This means Bob is 45 mtrs in front of Josh
    4*250 =1Km
    4*45 = 180 mtrs behind.
    180mtrs -final answer!! and I've used all my lifelines!!
    Sorry Buddy. No tricks in the wording. I'll give a hint tomorrow if still unanswered.
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    01 Jul '20 21:01
    @joe-shmo

    136m?
  13. R
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    01 Jul '20 21:16
  14. R
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    01 Jul '20 21:264 edits
    Solution:

    For every 250 meters Bob goes, John Goes 225 meters.

    When Bob has traveled 1000 meters ( The end of the race for Bob ), John has travled 225*4 = 900 meters

    For every 500 meters John travels, Josh travels 480 meters.

    At the time Bob crosses the finish line Josh has traveled:

    480*( 900 / 500 ) = 864 meters

    Thus, the distance between Bob and Josh at the finish is:

    1000 meters - 864 meters = 136 meters

    Problem taken from:

    https://brilliant.org/problems/winning-is-not-the-strategy/
  15. R
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    01 Jul '20 21:37
    More racing Problems:

    A, B, and C are running a race. The probability of A winning is twice that of B winning. The probability that B winning is twice that of C winning. The probability of any ties is zero. What is the probability "A" wins the race?
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