SOLUTION: Suppose you buy flour and cornmeal in bulk to make flour tortillas and corn tortillas. Flour cost $1.50/lb. Cornmeal cost $2.50/lb. You want to spend less than $9.50 on flour and c

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Question 733744: Suppose you buy flour and cornmeal in bulk to make flour tortillas and corn tortillas. Flour cost $1.50/lb. Cornmeal cost $2.50/lb. You want to spend less than $9.50 on flour and cornmeal, and you need at least 4 lb altogether.
a. Write a system of inequalities that describes this situation.
b. What are 2 possible solutions to this situation?

Found 2 solutions by josmiceli, fcabanski:
Answer by josmiceli(19441) (Show Source):
You can put this solution on YOUR website!
Let = pounds of flour needed
Let = pounds of cornmeal needed
Let = cost

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(1)
(2)
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I can see that , so

and

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and

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Solutions:
So, I can say and
and, also and
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check:
and
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(1)
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(2)
(2)
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OK

Answer by fcabanski(1391) (Show Source):
You can put this solution on YOUR website!
Problems like this require two equations. The first equation describes the amount. The second equation describes cost.

Call flour f and cornmeal c.

f + c >= 4 - the total amount is greater or equal to 4 lbs. You need at least 4 lbs - 4 lbs or more.

1.5f + 2.5c < 9.50 - the cost of each is # of lbs times the cost per pound. And their sum must be less than $9.50.

Solve the first equation for f in terms of c, then replace f in the second equation with that value.

f >= 4 - c.

Since it's greater than or equal to 4-c, one valid solution results from it being equal. So just use equal.

1.5(4-c) + 2.5c < 9.50

6 - 1.5c +2.5c < 9.50

c < 3.5

Replace a valid value into the f = 4-c equation. 3 is less than 3.5.

f = 4-3 = 1.

Another solution is c = 2 lbs (that's less than 3.5)

f = 4-2 = 2.