Complete Question
A set of magical wand prices are normally distributed with a mean of 50 dollars and a standard deviation of 4 dollars. A blackthorn wand has a price of 45.20. What proportion of wand prices are lower than the price of the blackthorn wand? You may round your answer to four decimal places
Answer:
0.1151
Step-by-step explanation:
We solve using z score formula
z = (x-μ)/σ, where
x is the raw score = $45.20
μ is the population mean = $50
σ is the population standard deviation = $4
We are solving for x < 45.20
Hence:
z = 45.20 - 50/4
z = -1.2
Probability value from Z-Table:
P(x<45.20) = 0.11507
Approximately to 4 decimal places = 0.1151
Therefore, the proportion of wand prices that are lower than the price of the blackthorn wand is 0.1151
Answer:
7x^2 + 14x - 12
Step-by-step explanation:
Add like terms:
(4x + 8x - 5) + (3x2 + 6x - 7) becomes:
4x^2 + 8x - 5 or (grouping like terms in columns):
+ 3x^2 + 6x - 7
---------------------
7x^2 + 14x - 12
Step-by-step explanation:
304
plug 4 in for x
3(4)^2 + 4(4)^3 = 304
48 + 256 = 304
Answer:
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Step-by-step explanation:
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plug the value of y
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Add the numbers: 12 and 7
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Hope I helped!
Best regards! :D
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