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)
__
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.
Answer:
Step-by-step explanation:
Tube support Length 
Weight 
Diameter 
Generally the equation for stress is mathematically given by
Where
Therefore
Generally the equation for Elongation is mathematically given by
Answer:
Step-by-step explanation:
if he rode 4 miles in 20 minutes
1h=20*3=60 min
4*3=12 miles/hour
They are both correct! Michael's equation is just a distributed version of Laurie's equation. Laurie's equation is solved like this: First distribute to get
2x + 1.2 + 0.8 + 0.7, then add the numbers together to get 2x + 2.7.
Michael's equation also starts with distributing to get 2x + 1.2 + 0.8 + 0.7 and adding the numbers together to get the same answer: 2x + 2.7. Hope this helps!
