Work rate problems

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  • Опубліковано 7 лют 2025
  • In this video I go through two work rate problems, and point out why I think this can often be a confusing topic.

КОМЕНТАРІ • 18

  • @sarahmina1442
    @sarahmina1442 2 роки тому +4

    Great explanation thank you! 💐

  • @teaformulamaths
    @teaformulamaths 2 роки тому +2

    Good topic! It's like the christmas cracker riddles

  • @jclarkmathclass9529
    @jclarkmathclass9529 3 роки тому +2

    All you have to do is multiply the two numbers for the numerator and add them for the denominator (working against you subtract).

  • @sarahmina1442
    @sarahmina1442 2 роки тому +2

    This question is very popular in GRE.
    Which level is it ?

  • @MrRandominternetname
    @MrRandominternetname Рік тому +1

    90*120 / 90+120 = 51.43 minutes. No fractions needed

  • @TeniolaTheLady
    @TeniolaTheLady 4 роки тому +2

    why do 2/3 km/hour? i dont get it, wont you do 1km/ 1.5?

    • @mathonify
      @mathonify  4 роки тому +2

      firstly 2/3 = 1/1.5. I think you got that already. I changed it to 2/3 kilometres per hour, because that is how we usually represent speed, in km/hr or miles/hr. We don't usually say our speed as 1km/1.5 hours.
      Also, to solve the problem you need the speeds to be in a common ratio, either km per hour or hours per km. Either way the ratios need to be the same. If you keep the speed as 1km/1.5 hours, then you need to change Tim's speed to km/1.5 hours which would then be 0.75km/1.5 hours. You could solve it this way also. There is nothing wrong with that, I just think writing the speed in km/hr makes more sense. Good question though. Maybe you are more used to seeing speed as miles per hour?

  • @Sam-xq1wb
    @Sam-xq1wb Рік тому

    Why do you swap the fraction around to figure out time?

    • @yalexyalex2782
      @yalexyalex2782 Рік тому

      If you have 7/6 t and you want to isolate t, you have to change the subject.

  • @ciarinenasinya1838
    @ciarinenasinya1838 2 роки тому +1

    Thankyou Sooo much

  • @isha9300
    @isha9300 4 роки тому +2

    I don't get why you did the second question when it's the same problem and answer except different wording.

    • @mathonify
      @mathonify  4 роки тому +5

      I was trying to make a point about how you can think about these types of questions. Maybe it didn’t work 🤷‍♂️

  • @rudolfgowaseb9804
    @rudolfgowaseb9804 Рік тому +1

    Make it to eszy

  • @shuchiakter4676
    @shuchiakter4676 Рік тому +1

    Ohioan tuitions be like:

  • @wat4504
    @wat4504 3 роки тому +1

    Wouldnt the answer for the first problem just be 2 hours? Them traveling together isnt going to increase Tim's speed

    • @mathonify
      @mathonify  3 роки тому

      It’s the time for them to travel 1km in total. As in Tim might travel 600m and John 400m, so in total they have traveled 1km.
      You could think of it as if they start 1km apart and walk towards each other, how long would it take for them to meet up.

    • @wat4504
      @wat4504 3 роки тому +2

      @@mathonify Ah, 1km as the total distance traveled of the two. That makes more sense, thank you