Can you solve this ? - Creative Thinkers Only !!!!!!!

MihiCherub

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    :cool:
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    bid87

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    Answer ...

    Q1. In miles per hour, what is the average rate of a car going 20 mph and traveling back the same distance at 60 mph?


    if we consider the car is driven for 1 hour.

    Original direction - 20 miles (time taken 1 hour)
    Coming back - 20 miles (time taken 20 minutes - 60*20/60)

    Total distance = 40 miles
    Total time taken = 80 minutes or 1.33 hours

    Average rate = 40/1.33 = 30.08 miles per hour
     

    MihiCherub

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    if we consider the car is driven for 1 hour.

    Original direction - 20 miles (time taken 1 hour)
    Coming back - 20 miles (time taken 20 minutes - 60*20/60)

    Total distance = 40 miles
    Total time taken = 80 minutes or 1.33 hours

    Average rate = 40/1.33 = 30.08 miles per hour
    correct...
    11.gif


    Average rate is not the average of the rates,
    the distance does not need to be known. Where a and b are the two rates, the average rate can be shown to be
    2ab/(a + b), so 2(20)(60)/(20 + 60) = 30.

    Average rate = Total distance/Total time.
    Let’s say the distance is D one way. Then the total distance is 2D.
    Let’s say the time the car travels 20 mph is t and the time the car travels 60 mph is T.
    Then from the formula Rate × Time = Distance, 20 × t = D and 60 × T = D.
    This gives you t = D/20 and T = D/60.

    So the total time is,
    t + T = D/20 + D/60. This is equal to t + T = 80D/1,200 = D/15.

    So the average rate = 2D/(t + T) = 2D/(D/15) = 30.
     

    ewmdyn

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    Using the letters "A,A,E,E,I,I,M,M,P,P,T,T" complete this grid with valid words. The grid reads the same across as down.

     

    ewmdyn

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    If you are in a dark room with a candle, a wood stove and a gas lamp.


    You only have one match, so what do you light first?



    plz don't say that you will gonna light a siga:rofl:
     
    Last edited:

    ewmdyn

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    Teanchi and Beanchi are a married couple (dont ask me who he is and who she is)!
    They have two kids, one of them is a girl. Assume safely that the probability of each gender is 1/2.

    What is the probability that the other kid is also a girl?


    Hint: It is not 1/2 as you would first think.
     
    Last edited:

    MihiCherub

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    If you are in a dark room with a candle, a wood stove and a gas lamp.

 You only have one match, so what do you light first?
    I'd light the match first so I can light the candle, then use the candle to light everything else, If needed. :)

    Ask questions which cannot be googled.
     

    epw

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    Teanchi and Beanchi are a married couple (dont ask me who he is and who she is)!
    They have two kids, one of them is a girl. Assume safely that the probability of each gender is 1/2.

    What is the probability that the other kid is also a girl?


    Hint: It is not 1/2 as you would first think.

    1/4