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
=(-4/5)^2 * -3/50
square -4/5 first; remember -4/5^2 is the same as -4/5 * -4/5
=(-4/5 * -4/5) * -3/50
multiply -4 numerators; multiply 5 denominators
=(-4 * -4)/(5 * 5) * -3/50
=16/25 * -3/50
multiply numerators 16 & -3; multiply denominators 25 & 50
=(16 * -3)/(25 * 50)
= -48/1250
simplify by 2
= -24/625 (or -0.0384)
ANSWER: -24/625 (or -0.0384)
Hope this helps! :)
Answer:
3 is not a function because you cant have the same input with different outputs
4 is a function because each input has one output
Step-by-step explanation:
-0.25 would be -25/100 which can be reduced to -1/4
Answer:
(r + 20)t = r
Step-by-step explanation:
Distance is constant in the scenario above, distance from home to wedding and wedding back home is the same.
From wedding back home. :
Recall : Distance = speed * time
Distance = r * 1 hour
From home to wedding :
Speed = 20 mph more ; r + 20
Time = t
Distance = (r + 20)* t = (r +20)t
Since the distance are the same, we can equate both :
(r + 20)t = r * 1
= (r + 20)t = r
