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Inequation problem

  1. Mar 26, 2004 #1

    I'm stuck in a school assignment and would like some advice if it's not to much bother.

    Jim makes high energy biscuits using peanuts and chocolate chips. Jim wanted to make a maximum of 400g of biscuits but wanted the biscuits to contain at least 180g of carbohydrates

    If we let the mass of the peanuts be p and the mass of the chocolate chips be c, writen an inequation to represent the fact that the total mass must be less than 400g. Assume the mass of chocolate chips is the range(y) and the mass of peanuts is the domain(x)

    My answer:

    Mass of peanuts = p Mass of chocolate chips = c

    p + c < 400

    c < 400 - p

    Hope that's right

    The peanuts provide 30% of their mass in carbohydrates and the chocolate chips provide 60% of their mass in carbohydrates. Write an inequation that represents the fact that the mass of carbohydrates must be greater than 180g.

    My answer:

    0.30p + 0.60c > 180

    0.60c > 180 - 0.30p

    Any comments will be much appreciated .
    Thanks :smile:
    Last edited: Mar 26, 2004
  2. jcsd
  3. Mar 26, 2004 #2
    Looks good to me.

    For the last inequality you had,

    .60c > 180 - .30p

    you might want to divide through by .6 in order to get an expression for only c, i.e.

    c > 300 - .5p


    Edit: Fixed.
    Last edited: Mar 26, 2004
  4. Mar 26, 2004 #3


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    I think cookiemonster has the inequality going the wrong way.

    Anyways, do you think you can make the next step, and figure out the range of allowable masses for the peanuts and chocolate chips?
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