9514 1404 393
Answer:
- x+y=70; 8.50x+12.50y=10.56(70)
- 36 pounds Antigua
- 34 pounds Rift
Step-by-step explanation:
At the insistence of the problem author, we will let x represent pounds of Antigua coffee and y represent pounds of Rift coffee. Then we have ...
x + y = 70
8.50x +12.50y = 10.56(70) . . . . . total cost of the mix
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We like to use the variable to represent the high-cost contributor. Here, that is y, so we'll substitute for x:
x = 70-y
8.50(70 -y) +12.50y = 10.56(70)
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595 +4y = 739.2 . . . . . . . . . . . . . . simplify
4y = 144.2 . . . . . . . . . . . subtract 595
y = 36.05 . . . . . . . divide by 4
x = 70 -36.05 = 33.95
About 36 pounds of Rift Valley coffee and 34 pounds of Gualtemala Antigua coffee must be mixed.
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<em>Additional comment</em>
By letting the variable in our equation 8.50(70 -y) +12.50y = 10.56(70) represent the high-cost coffee, we ensure that the simplified equation will have a positive coefficient for the variable. This means we don't have to mess with negative numbers, so eliminating a common source of math errors.
The problem requirement that we use x for the low-cost contributor meant we introduced an extra equation that would not have been needed.
Ok then after that what’s the question ?
The answer is y=-8+11/-4x.
or y=11/-4x+(-8).
-5.4c (I am not quite sure if I am correct)
Answer:
Step-by-step explanation:
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