1. #1
    Brewmaster Breccia's Avatar
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    Deathwing Ate My Homework

    Two warriors, identical in most respects, are crossing the stone bridge in Deadwind pass heading from Duskwood towards the Swamp of Sorrows. When they are exactly one-quarter of the way along the bridge, they hear a mighty roar behind them: Deathwing is flying in from the west, heading towards Deadwind pass to destroy the bridge and anything still on it. When spotted, Deathwing is exactly one bridge length away from the bridge's western end and moving east towards them awfully, awfully fast.

    Jumping off the bridge is not an option. Falling molten chunks of the bridge would surely kill them as they flailed around in the water...assuming they landed in water and not jagged rocks, that is. The only way to survive is to make it off the bridge in either direction: towards Deathwing, or away.

    Warrior A takes the direct, albeit risky, approach and immediately turns and runs straight towards Deathwing. Speed and luck are on his side, because he reaches the end of the bridge, turns to the left and makes it two more yards before Deathwing reaches the bridge, and therefore, escapes with his life. At this point, Deathwing starts breathing fire straight down as he travels over the length of the bridge.

    Warrior B took the more obvious, if cowardly, solution and immediately started running towards the far end of the bridge, away from Deathwing. He was able to cover a great portion of the bridge's length, but soon, the flames of Deathwing were right behind him. The very instant the flames were just about to touch him, Warrior B uses Heroic Leap (40 yard range) and makes it exactly to the end of the bridge. There, he has plenty of time to run to the side and get to safety.

    Calculate the length of the bridge, to the nearest inch.

    Notes:
    -- both warriors are moving at identical speeds. I did not, however, tell you if their speed was improved or penalized by any ongoing effects, so the in-game knowledge of movement speed (7 yards a second, or so) is not necessarily correct.
    -- Deathwing's speed is unknown but much, much faster than the warriors.
    -- Assume that Deathwing's flame is directly beneath him and has no effective radius (i.e. it's a 2-dimensional wall of firey death)
    -- Pretend the entire problem is on a straight line. As long as everyone is on the same path (i.e. rails) it's the same problem anyhow.

    Breccia

  2. #2
    I'm pretty sure that without knowing any speeds or how long it all took, you can't solve it. =p

  3. #3
    if they were on the middle of the bridge when making that decision (it feels implied) then the bridge would be 80 yards, or 240 ft, or 2880 in, since jumping from there to the edge of the bridge was 40 yards.

    the rest of the information doesn't seem useful as it mentions speed, but not actual numbers.

  4. #4


    Please don't spam with images.
    Last edited by Splenda; 2011-10-01 at 04:07 AM.

  5. #5
    Blademaster Baradur's Avatar
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    well, the first warriors speed = x
    Deathwing's speed =4x
    1/4 of the bridge = x+2
    3/4 of the bridge = x+40
    x+40=3x+2
    38=2x
    x=19
    bridge length=4x+2
    so the length of the bridge should be 78 yards=234ft=2808in

    As to Teroseth below me, awesome reply, but please don't send the OP flying into the chasm til he posts the actual answer, if he ever does.
    Last edited by Baradur; 2011-10-01 at 05:19 PM.
    The people with the most to say generally know the least.
    I prove the above statement.

  6. #6
    Dreadlord Teroseth's Avatar
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    European or African Warrior? Laden or unladen?

  7. #7
    Brewmaster Breccia's Avatar
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    Quote Originally Posted by Baradur View Post
    but please don't send the OP flying into the chasm til he posts the actual answer, if he ever does.
    Here it is:

    The speed of the warriors and Deathwing are unknown, and other than that Deathwing is faster, there is no known relationship. Therefore the speed of the warriors will be called W, and Deathwing's speed D. The length of the bridge, in yards, will be called B.

    If two objects both move for the same amount of time, then the ratio of their speeds is the same as the ratio of their distances travelled. The time it takes Deathwing to reach the bridge, is the same as the time Warrior A needs to travel one-quarter of the bridge's length, plus 2 more yards. Therefore the first ratio is

    W/D = 0.25B + 2/B

    The time it takes Deathwing to reach the bridge, then also get to the spot where Warrior B has to jump (40 yards shy of the end of the bridge), is the same as the time it takes Warrior B to reach that same spot himself. Warrior B is travelling at the same speed, so therefore the second ratio is

    W/D = 0.75B - 40/2B - 40

    As W/D is the same in both cases, we can set the two equal to each other.

    (0.25B + 2)/B = (0.75B - 40)/(2B-40)

    (0.25B + 2)(2B - 40) = (0.75B - 40)B

    0.5B^2 - 10B + 4B - 80 = 0.75B^2 - 40B

    0.5B^2 - 6B - 80 = 0.75B^2 - 40B

    0 = 0.25B^2 - 34B + 80

    0 = B^2 - 136B + 320

    The quadradic formula will take us the rest of the way.

    B = 133.6049 or 2.3951 yards

    Obviously the second answer doesn't make sense, since Warrior B needed to use Heroic Leap to escape. Therefore the answer rounds to 133 yards, 1 foot, 10 inches.

    Edit: as this was a translated problem, certain WoW factors (such as keyboard turning and hitbox size) are not taken into consideration, but the overall idea remains.
    Last edited by Breccia; 2011-10-02 at 09:06 PM.

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