Answer:
<h2>x = 4 and y = 2 or x = 10 and y = 4</h2>
Step-by-step explanation:





Answer:
P(X < 80) = 0.89435.
Step-by-step explanation:
When the distribution is normal, we use the z-score formula.
In a set with mean
and standard deviation
, the zscore of a measure X is given by:

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.
In this question, we have that:

P(X < 80)
This is the pvalue of Z when X = 80. So



has a pvalue of 0.89435.
So
P(X < 80) = 0.89435.
Answer:
B
Step-by-step explanation:
I just did it Red Riot out
Answer: 9+4n-1 = 20
We can solve this by substitution.
Replace n with the value given, 3 (remember 4n means 4 times n):
9 + 4*3 - 1
Then work it out using arithmetic
9+12-1
=20
Answer:
A number minus the product of
4
and its reciprocal is less than zero. Find the numbers which satisfy this condition.
AAny number less than
−
2
or between
0
and
2
BAny number between
−
2
and
2
CAny number less than
2
DAny number between
0
and
2
Solution
Let the number be x
Then
x
−
(
4
×
1
x
)
≤
0
⇒
x
≤
4
x
⇒
x
2
≤
4
⇒
|
x
|
≤
2
⇒
−
2
≤
x
≤
2
Step-by-step explanation: