40 lb sugar @ $1/lb, 200 lb flakes @ $0.60/lb; find $/lb of

igor_iv837

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Find the cost per pound of sugar-coated breakfast cereal made from 40 lb of sugar that cossts $1.00 per pound and 120 lb of corn flakes that cost $.60 per pound.

I put on chart.
Amount-40 lb, 120 lb, the sum of it 160lb
Cost $1.00, .60 .

160.6=160 ............its wrong :(
 
Definition of "cost-per-pound"

Hi:

Cost-per-pound is easy to calculate if you know the total cost and the total pounds. You simply divide the cost by the weight.

If I buy 10 pounds of potatos for $4, then to find out how much I paid for each of those pounds, I divide the cost ($4) by the weight (10 lbs).

4/10 = 2/5 = 0.4

The potatos cost 40 cents per pound.

If I take six garbage bags filled with crushed aluminum pop cans to the recycling center, how much money do I get per pound?

Well, in order for me to calculate this amount, I need to know both the total amount of money I get and the total weight of all the cans. Let's say that they give me $4.37. I ask them how much the cans weigh, and they tell me 19 pounds.

The cost-per-pound is the total amount of money divided by the total weight.

4.37/19 = 0.23

I received 23 cents per pound.

The word "per" indicates a ratio. A ratio is a fraction.

When you read "cost-per-pound", you can think: cost/pound (as in cost divided by pounds).

Okay, so in your exercise, you need both the total value of the finished product (sugar-coated flakes) and the total weight of the finished product. Dividing this value by this weight gives you the value of each pound (cost-per-pound).

You wrote that the total weight is 160 pounds. That is correct!

Next, you need to calculate the total value of this 160 pounds of sugar-coated breakfast garbage.

How do you do that?

Well, if you were sugar coating this stuff, then you had to pay the sugar company $1 for each pound of sugar you purchased, and you had to pay the corn-flake company $0.60 for each pound of corn flakes you purchased. Let's do the math on this.

40 * $1 = $40 for the sugar.

120 * $0.60 = $72 for the cornflakes.

So, how much total money did you pay to buy the stuff to make sugar-coated corn flakes?

If you divide this total amount of money by the total weight of the sugar-coated corn-flakes, then you will get the cost-per-pound.

Please show me your work in finishing these last two steps.

Cheers,

~ Mark :)


PS: The dogs have wrapped a leash around my ankle, and they are trying to drag me outside for a walk. I will be away from the computer for a couple hours ...
 
igor_iv837 said:
160.6=160 ............its wrong :(
Since 160.6 cannot equal 160 (they are different numbers), then this "solution" would of course have to be wrong.

Meanwhile, you were asked to find a cost per pound. Rather than inventing untrue "equations", why not try finding the required value? One could use the exact same reasoning as was outlined for you, step by step, for your other, almost exactly the same, cost-per-pound exercise that you'd posted just a few hours earlier. :?

Eliz.
 
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