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Motion problem in mathematics?

Kirk's average driving speed is 10 miles per hour faster than Mia's. In the same length of time it takes Kirk to drive 354 miles. Mia only drives 294 miles. What is Kirk's average speed?

7 Answers

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  • ?
    Lv 7
    1 decade ago
    Favorite Answer

    k = m+10

    354 miles × 1 hour/k miles = 354/k hours

    294 miles × 1 hour/m miles = 294/m hours

    354/k = 294/m

    354m = 294k

    354m = 294(m+10)

    60m = 2940

    m = 49 miles/hour

    k = 59 miles/hour

    Kirk averages 59 miles/hour

  • 1 decade ago

    let mia's speed be x, kirks speed =x+10.

    given for time ' t ' distance travelled by kirk= 354 & by mia 294.

    hence kirk speed =dist/time; 354/t. =x+10 1

    mia's speed =294/t = x 2

    1/2 gives

    354/294 = (x+10)/x = 1+ 10/x

    or 10/49 = 10/x;

    x= 49= mia's speed

    kirks = 59

  • Anonymous
    1 decade ago

    If Mia's speed is x than Kirks is x + 10

    distance = speed x time or time=distance/speed

    Since both took same time then

    Mia's time 294/x = 354/(x+10) kirks time

    294(x+10) = 354x

    294x + 2940 = 354x

    2940 = 60x

    2940/60 = x just divide to find x

  • 1 decade ago

    Let the speed of M is a km/h,thus the speed of K will be (a + 10) km/h

    Let the time is t hour,thus :-

    (a +10) x t = 354-------------(i)

    & a x t = 294----------------------(ii)

    Now at + 10t = 354 by eq (i)

    =>294 +10t = 354

    =>10t = 354 - 294 = 60

    =>t = 60/10 = 6 hour

    by putting this value in eq (i)

    =>(a + 10) x 6 = 354

    =>(a + 10) = 354/6 = 59 km/h is the required answer.

  • 1 decade ago

    in some time (we will figure it) Kirk drove 354-294 = 60 miles farther.

    Since Kirk had been going 10 mph faster, they must have been driving for 60miles / 10mph = 6 hours.

    Now just divide Kirk's distance by the time elapsed. 354miles / 6hrs = his average speed in mph.

  • koloc
    Lv 4
    4 years ago

    For InSearch (2 solutions under): i presumed the airplane velocity contains the wind velocity, consequently with the wind at the back of it, it replaced into going 240 km/hr, no longer 240 km/hr + Wind km/hr. interpreting the question extra heavily, it does say the "average air velocity", so I agree collectively with your calculation InSearch, 40 8 km/hr.

  • 1 decade ago

    speed=Distance/time

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