How to solve simultaneous equation word problems

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  • Опубликовано: 6 сен 2024

Комментарии • 37

  • @ABWEndon
    @ABWEndon 9 лет назад +2

    Thank you Simon. Very well explained and although my brain hurts a little, I can feel that it has done me some good!

  • @bolloxmagee4409
    @bolloxmagee4409 8 лет назад +1

    very helpful! thanks! I've not been listening to my teacher all year, and our end of the year exams are tomorrow, so I binging math videos XD! I'm the biggest procrastinater ever!

    • @3minutemaths
      @3minutemaths  8 лет назад +2

      +Bollox Magee - Glad to help and all best S :-)

  • @3minutemaths
    @3minutemaths  11 лет назад

    Hi Mustanser - glad you liked the video and thanks for the comment :-)
    The first equation is F = 3S . The second is a little more difficult. Imagine 10 years ago ... at that stage the father would be F - 10 and the son would be S - 10.
    However the dad is 5 times older so F - 10 = 5 (S - 10). Now you've got two equations F = 3S (or F - 3S = 0) and F - 10 = 5S - 50 (or F - 5S = -40). Take equation 2. away from equation 1. You should end up with the son aged 20 and the dad aged 60. All best S

  • @3minutemaths
    @3minutemaths  11 лет назад

    Hi Glen - when I posted this it took out the new lines and doesn't look as neat. I hope you can follow. If not please send your email address through mathswrap and I'll send a reply.

  • @3minutemaths
    @3minutemaths  11 лет назад

    Hi - Q2 needs a bit more explanation. If you email me through Maths Wrap I'll send a solution. In the meantime Q1:
    You've got 2 equations J = 2L and J + L = 5L - 48.
    So, change both and you'll get J-2L = 0 and J-4L = -48. Then take eq2 from eq1 and you should get -2L = -48. So L = 24.
    Put L=24 back into eq1 and J = 48.
    So Jan is 48 and Lisa is 24.
    I hope this helps and all best S

  • @moraaataya2470
    @moraaataya2470 9 лет назад

    This is positively effective. I like it.

  • @boogs7115
    @boogs7115 9 лет назад

    a and b are positive whole numbers.
    find value of a and b to make the solution to this equation x=4
    a(x+1)+b(x-2)=16 please help me if you can :)

  • @3minutemaths
    @3minutemaths  11 лет назад

    Hi Glen - you've got two equations:
    C + Z = 25
    3.2C + 1.4Z = 62
    Multiply first by 3.2 (and leave second) so:
    3.2C + 3.2Z = 80
    3.2C + 1.4Z = 62
    Take second from first, so:
    1.8Z = 18
    Therefore Z = 10
    Then put back into
    C+ Z = 25
    C + 10 = 25
    So C = 15
    The alloy has 15kg of copper and 10kg of zinc.
    I hope this helps and thanks for the question.
    All best
    S

  • @pakistaniart4666
    @pakistaniart4666 6 лет назад

    It's very helpful thanks sir

  • @galib0262
    @galib0262 9 лет назад

    I hav given a symultaneous equation word problem it would be a grateful if you kindly give the solution of the following question:
    At a shooting range, each shot costs 20c. If you hit the target, you receive 30c. Mira has 20 shots and makes a loss of 70c. How many hits did she get?

    • @3minutemaths
      @3minutemaths  9 лет назад

      ABDUL JAWAD Ghalib Hi - you need to set up an equation to solve (not a simultaneous equation though) as follows:
      30x - 400 = -70
      30 is the amount received for a hit
      x is the number of hits
      400=20x20 is the money paid for 20 attempts
      -70 is the total loss
      The solution to this equation is x=11; in other words Mira gets 11 hits.
      Hope this helps and all best S :-)

    • @galib0262
      @galib0262 9 лет назад

      Simon Deacon, thnx 4 da solution, it was really helpful n i hav understood wat u hav explained. In future i will ask 4 help if i face any problem. :)

    • @3minutemaths
      @3minutemaths  9 лет назад

      ABDUL JAWAD Ghalib No worries :-)

  • @mymindydiditong
    @mymindydiditong 11 лет назад

    Hi, im not sure how to solve these teo problems:
    1)Jan is twice as old as Lisa. The sum of their ages is 5 times Lisa's age minus 48. How old are they now?
    2)John received changes worth $13 all in coins. He received 10 more dimes than nickles, and 22 more quarters than dimes. How many coins of each did he receive?

  • @kurtissankey7922
    @kurtissankey7922 9 лет назад

    having trouble with this one A television repair person charges a service call of $36 and then a further $28 per hour. An electrician charges a service call of $24 and then a further $36 per hour. Use simultaneous equations to calculate the number of hours each person worked to charge the same total fee. What is the fee?

  • @gamingwithahmed8235
    @gamingwithahmed8235 8 лет назад

    Thanks really useful and please tell me the equation for solving linear equation simultaniously

    • @3minutemaths
      @3minutemaths  8 лет назад +1

      +GamingwithAhmed - Hi - here's the playlist and glad to help :-) ruclips.net/p/PLPglScc3TJ-PkkPq8fL81mx0-eC7WzmUi

  • @mustanserhussain2595
    @mustanserhussain2595 11 лет назад

    Hey,this was very useful indeed,thankyou.Can u give me the solution for this problem. A man is 3 times the age of his son.10 years aga he was five times the age of his son.Find their ages by finding the value of x.

  • @stephenbarker100
    @stephenbarker100 10 лет назад +1

    how would i solve x squared + y squared = 29
    and y _ x = 3

    • @3minutemaths
      @3minutemaths  10 лет назад

      Hi stephen barker ...
      xsquared + ysquared = 29
      y - x = 3
      is probably best solved by using substitution (rather than simultaneously). The 'tell' is y - x = 3. This is a fairly straightforward equation that I can manipulate so that y = x + 3.
      I'm now going to use y = x + 3 in xsquared + ysquared = 29.
      So, substitute x + 3 where I see a y:
      xsquared + (x + 3)(x + 3) = 29
      Then tidy up
      xsquared + xsquared + 6x + 9 = 29
      2xsquared + 6x - 20 = 0
      I then use cross method to factorise (see ruclips.net/video/m5pZN-oud5c/видео.html)
      (2x - 4)(x + 5) = 0
      So, x = 2 and x = -5
      This solution really needs you maths teacher to go through on a one to one. Hope it helps and all best S :-)

    • @stephenbarker100
      @stephenbarker100 10 лет назад

      its called the sine rule got angle of 83 degrees and sides of 11cm and 7.4 other is the cosine rule got 40 degrees angle sides of 8 cm and 9 cm
      can you give me any advice on this

    • @stephenbarker100
      @stephenbarker100 10 лет назад

      Simon Deacon
      need some indice advice

  • @mohamedabdelhalim6078
    @mohamedabdelhalim6078 10 лет назад

    thanks !!! really did help.could you solve this question for me please. A submarine can travel at 25 knots with the current and at 16 knots against it .Find the speed of the wind and the speed of the submarine in still water.

    • @3minutemaths
      @3minutemaths  10 лет назад

      Hi Mohammed - thanks for this. Probably the easiest way is to draw a quick sketch. As the submarine can travel at 25 knots with the current and 16 knots against it - in still water its speed should be the difference: 9 knots.
      Is there any more information with the question? Rgds S

  • @GabrielTobing
    @GabrielTobing 6 лет назад

    Can anybody help me with these questions?
    I figured out the first half, but can't figure out the second half.
    Find two numbers whose sum is 138 and whose difference is 88.
    Find two numbers whose sum is 36 and whose difference is 9.
    Answers:
    1) 25,113
    2) 22.5, 13.5
    THANKS!!!

    • @just_someone7667
      @just_someone7667 Год назад +1

      That 113 is the value of x, you should have gotten 2 equations
      (i) x - y = 88
      (ii) x + y = 138
      and you have 113 from previous workings, so you subtract 138 from 113 and you have 25
      so y = 25
      2x 226 = 113

  • @arabstyle23
    @arabstyle23 9 лет назад

    there is a question I found and I couldn't solve it please help me
    the cost oh hire a tent consists of two parts
    $C and $D per day ( there is a plus sign in the place of "and")
    total cost for 4 days is $27.1 and for 7 days $34.30
    write down the 2 equations

  • @nadaabdalla7411
    @nadaabdalla7411 11 лет назад

    would it still be correct if we wrote that the width is equal to -7.5?

  • @gron88671
    @gron88671 11 лет назад

    The materials to make 25kg of an alloy of copper and zinc cost $62. If the copper costs $3.20/kg and the zinc costs $1.40/kg, find the composition of the alloy.
    How would i do that problem?

  • @fararamlee4509
    @fararamlee4509 6 лет назад

    Y this equation have to (+) not (-) like others ??

    • @Matt-rocker
      @Matt-rocker 5 лет назад

      Fara Ramlee when you have 2 different signs( +, -) you add then as 2w-2w=0

  • @3minutemaths
    @3minutemaths  11 лет назад

    Hi ... hmm. There could be a way of getting a -7.5 if the width was also negative in your calculation. For most questions they would expect you to then convert to both positive numbers - and say the pool is 7.5m width. My email is on mathswrap - if you send me a copy (photo is fine) of your working - I'll mark and email back. Hope this helps. S

  • @mustanserhussain2595
    @mustanserhussain2595 11 лет назад

    ago*

  • @mymindydiditong
    @mymindydiditong 11 лет назад

    *two

  • @nintendocuprisunify
    @nintendocuprisunify 10 лет назад +3

    Fix the audio