Answer:
$14 per lb
Step-by-step explanation:
Given:
- Brand Y = $18 / lb
- Special Blend = $17 / lb
Let x be the price per lb of brand X coffee
3 lbs of brand X coffee + 9 lb of brand Y coffee = 12 lbs of special blend
⇒ 3x + 9(18) = 12(17)
⇒ 3x + 162 = 204
⇒ 3x = 42
⇒ x = 14
Therefore, brand X costs $14 per lb
→ You will pay $ 89.7.
The tip value is based on the bill value. Hence, to find the total payment you have to <u>multiply 78 by 1.15</u> (this includes the tip, 1.15).
Or you can <u>first find how many</u> 15% is from $78:
And then add this to $78:
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brainly.com/question/12901165
Step-by-step explanation:
a. we simply subtract 3. from 2.
x + 2y + z = 15
- -3x + y + z = 2
--------------------------
4x + y 0 = 13
b. we multiply 3. by 3 and then subtract from 1.
2x - 4y + 3z = -7
- -9x + 3y + 3z = 6
-----------------------------
11x - 7y 0 = -13
c. we multiply the result of a. by 7, and then simply add a. and b., because the y terms have different signs already.
28x + 7y = 91
+ 11x - 7y = -13
--------------------------
39x 0 = 78
39x = 78
x = 2
d. we use this x = 2 in the result of a.
4×2 + y = 13
8 + y = 13
y = 5
e. using x = 2 and y = 5 in 2.
2 + 2×5 + z = 15
2 + 10 + z = 15
12 + z = 15
z = 3
the solution is therefore (2, 5, 3).
Answer:
Step-by-step explanation:
We want to determine a 95% confidence interval for the mean total cholesterol level of all males.
Number of sample, n = 355
Mean, u = 185 mg
Standard deviation, s = 16
For a confidence level of 95%, the corresponding z value is 1.96. This is determined from the normal distribution table.
We will apply the formula
Confidence interval
= mean +/- z ×standard deviation/√n
It becomes
185 +/- 1.96 × 16/√355
= 185 +/- 1.96 × 0.849
= 185 +/- 1.66404
The lower end of the confidence interval is 185 - 1.66404 =183.336
The upper end of the confidence interval is 185 + 1.66404 = 186.66
Therefore, with 95% confidence interval, the mean total cholesterol level of all males is between 183.336 mg and 186.66 mg
Answer:
20 percent
Step-by-step explanation:
