Answer:
60
Step-by-step explanation:
First, divide 120 by two and get 60. Now do 120-60 to get 60. Set up proportion
60/x = x/60.
Cross multiply
x^2 = 3600
and now find the square root of 3600
60
15/x = 20/100
15*100 = 20*x
1500 = 20x
1500/20 = 20x/20
75 = x
15/75 = 20/100
the expected number of couples who met online is 75
60% please make me as the most brainlyest
Answer:
Solution: -∞ <x< ∞
Interval Notation: (-∞, ∞)
Step-by-step explanation:
Answer:
And using a calculator, excel or the normal standard table we have that:
Step-by-step explanation:
Previous concepts
Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".
The Z-score is "a numerical measurement used in statistics of a value's relationship to the mean (average) of a group of values, measured in terms of standard deviations from the mean".
Solution to the problem
Let X the random variable that represent the scores of a population, and for this case we know the distribution for X is given by:
Where
and
Since the distribution for X is normal then we know that the distribution for the sample mean
is given by:
We can find the individual probability like this:
And using a calculator, excel or the normal standard table we have that: