Answer:
y = -5/4x + 6
Step-by-step explanation:
Since the line we are supposed to find is parallel to y = -5/4x - 5 that means they are going to have the same slope. The line we are looking for is of the following type: y = -5/4 x + b
Since it passes through the point (-8,4):
4 = -5/4 * (-8) + b <=>
4 = -2 + b <=>
4 + 2 = b <=>
b = 6
Hence the line is going to be: y = -5/4x + 6
So first create and define your variables:
Z = amount of zebra fish
N = amount of neon tetras
Now create your equations:
2z+2.15n=31.20
z+n=15
This is your system. There are multiple methods to use but in this problem I’ll use the substitution method by simplifying the bottom equation.
2z+2.15n=31.20
z=15-n
Now I’ll plug the bottom equation into the top one.
2(15-n)+2.15n=31.20
And just solve from here.
30-2n+2.15n=31.20
0.15n=1.20
n=8
So he bout 8 neon tetras, and 15-8= 7, so he bought 7 zebra fish
Answer:
c) .22
Step-by-step explanation:
We have that to find our 
level, that is the subtraction of 1 by the confidence interval divided by 2. So:
Now, we have to find z in the Ztable as such z has a pvalue of 
.
So it is z with a pvalue of 
, so 
Now, find the margin of error M as such
In which 
is the standard deviation of the population and n is the size of the sample.
In this question:
Then
Answer:
true
Step-by-step explanation:
the second 7 is in the tenth place and the first 7 is in the hundredth place, which is 1/10 the tenth place
If it is a ratio of 3:5 you are dividing 480 into 8 parts (3+5).
So divide 480 by 8: 480/8 = 60
Then the ratio is (3x60):(5x60) or 180:300
To check it is correct, add up the two parts to see that they come to 480:
180+300 = 480. All good.
Hope this helps
