Answer: 126 samples
Step-by-step explanation:
Given that :
Standard deviation (σ) = 0.7
Mean (m) = 7.3
Error (E) = 0.08
α = 80%
The sample size n can be obtained using the relation :
n = [(Zcrit * standard deviation) / Error]^2
The Zcritical at 80% = 1.282
Hence,
n = ((1.282 * 0.7) / 0.08)^2
n = (0.8974 / 0.08)^2
n = 11.2175^2
n = 125.83230625
n = 126
First we distribute
into
and
.
That makes the left side of the equation
Now we subtract
from
, which makes
Now the equation is
Our goal is to isolate
, so we both sides by 30
That will make the equation
We multiply -1 on both sides of the equation:
Finally we simplify
, which makes
So the answer is
Answer:
X is =12
Step-by-step explanation:
Answer:
0.007x, where x is the percentage of vinegar.
Step-by-step explanation:
x% of the mixture is vinegar, but the value of x is missing!
x% of 0.7 = 0.7x/100 = 0.007x
There are 0.007x liters of vinegar in the container.
C+d=14
c-6=d
then you will plug c+6 in the first equation and you will get:
c+c-6=14
then you get
2c=20
c=10, so the cat is ten years old
the cat is 6 years older than the dog, so the dog is 4 years old
hope that helps :)