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    I'm stuck on Linear programming constraints in decision 1, I have no idea how the constraints thing works or how to answer questions using it, here is the constraints part I don't understand:


    I have no idea why the machines time constraint is 2x + 3y < 30
    Why would it be 2x + 3y < 30, I understand they got the 30 hours from the machine time but 2x + 3y all together = to 13 hours of machine time, why such a random number to make a constraint less than 30 on, I have no idea how they came up with this. Can anyone explain this to me i'm struggling
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    (Original post by Sayless)
    I'm stuck on Linear programming constraints in decision 1, I have no idea how the constraints thing works or how to answer questions using it, here is the constraints part I don't understand:


    I have no idea why the machines time constraint is 2x + 3y < 30
    Why would it be 2x + 3y < 30, I understand they got the 30 hours from the machine time but 2x + 3y all together = to 13 hours of machine time, why such a random number to make a constraint less than 30 on, I have no idea how they came up with this. Can anyone explain this to me i'm struggling
    Remember that x is the number of type A machines that are made and y is the number of type B machines that are made. So 2x for example could represent 2 hours spent on the machine.

    30 hours is the total machine hours available.

    How many machine hours does type A take to make per unit? How about type B?

    So 30 hours are available, and if x represents the number of type A units made and y the number of type B units, and have the whole equation with time as their units (not that it matters but to understand) then the inequality becomes 2 hours * x (number of type A units made) + 3 hours * y (number of type B units made) and they have to be less than or equal to 30.

    So you could concentrate all of your time on 15 type A's and 0 type B's (giving 15 * 2 + 0 * 3 = 30) or the other way around.
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    (Original post by SeanFM)
    Remember that x is the number of type A machines that are made and y is the number of type B machines that are made. So 2x for example could represent 2 hours spent on the machine.

    30 hours is the total machine hours available.

    How many machine hours does type A take to make per unit? How about type B?

    So 30 hours are available, and if x represents the number of type A units made and y the number of type B units, and have the whole equation with time as their units (not that it matters but to understand) then the inequality becomes 2 hours * x (number of type A units made) + 3 hours * y (number of type B units made) and they have to be less than or equal to 30.

    So you could concentrate all of your time on 15 type A's and 0 type B's (giving 15 * 2 + 0 * 3 = 30) or the other way around.
    AHhh i get it now ,so the numbers 2 and 3, represent the machine time hours.
    that makes sense now thanks i just thought they meant the amount of type A or something idk thanks
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    Hi
    Dose every school do A/L maths D1?
    Thank you
 
 
 
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