What magic trick??
Are you gonna do a magic??
Sorry for a lot of questions.
A=xy
If there is 10% increase in x then,
New value of x = x + 10%of x =1.1x
similarly for y
New value of y after increase= 1.1 y
New value of A after increase in x and y = 1 .1x × 1.1 y= 1.21xy
now
increase amount in A= New value of A - old value of A
=1.21xy - xy= 0.21xy
percentage increase in A= (0.21xy÷xy )× 100= 21%
10x^2 - 25 = x^2
Take the square root of each side.

x = 10x - 5i
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:
The value of test statistic is 1.338
Step-by-step explanation:
We are given the following in the question:
Population mean, μ = 16.000
Sample mean,
= 16.218
Sample size, n = 22
Alpha, α = 0.05
Sample standard deviation, s = 0.764
First, we design the null and the alternate hypothesis
We use one-tailed t test to perform this hypothesis.
Formula:
Putting all the values, we have
Thus, the value of test statistic is 1.338