Answer:
6
Given expression:
Simplify following inside parenthesis
If following is |-a| then |-a| = a
Evaluate following
Answer:
- $52
- this estimate is a little low
Explanation:
a) I might choose 6 1/2 hours and $8 per hour, so the estimated earnings would be ...
6(8) +(1/2)(8) = 52 dollars . . . . estimated earnings
These values are purposely chosen so that one is a little high and the other is a little low, hopefully producing a closer estimate than if both numbers were high (as 7 hours, $8, for example).
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b) Using 800 instead of 790 means the pay estimate is about 1/80 = 1.25% high.
Using 6 1/2 instead of 6 3/4 means the hours estimate is about 1/27 ≈ 3.7% low.
So, we expect the product of these values to be slightly low, perhaps by about 2.5%.
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<em>Comment on estimating</em>
If you can estimate the error in the estimate with some reasonable accuracy, you can use that to adjust the estimate to a pretty close value.
Answer:
p=2
Step-by-step explanation:
−4p=11−19
−4p=−8
then you divide both sides by -4 and two negatives make a positive.
Let x be the amount of Columbian coffee in the mixture and y the amount of Sumatra coffee in the mixture, then
x + y = 1 . . . (1)
9.25x + 14.25y = 12.50 . . . (2)
(1) x 9.25 => 9.25x + 9.25y = 9.25 . . . (3)
(2) - (3) => 5y = 3.25 => y = 3.25/5 = 0.65
From (1), x + 0.65 = 1 => x = 1 - 0.65 = 0.35
1 pound of the mixture contains 0.35 Columbian coffee and 0.65 Sumatra coffee
Therefore, 12 pounds of the mixture will contain 0.35 x 12 = 4.2 pounds of Columbian coffee and 0.65 x 12 = 7.8 pounds of Sumatra coffee
