Answer:
The 80% confidence interval for the the population mean nitrate concentration is (0.144, 0.186).
Critical value t=1.318
Step-by-step explanation:
We have to calculate a 80% confidence interval for the mean.
The population standard deviation is not known, so we have to estimate it from the sample standard deviation and use a t-students distribution to calculate the critical value.
The sample mean is M=0.165.
The sample size is N=25.
When σ is not known, s divided by the square root of N is used as an estimate of σM:
The degrees of freedom for this sample size are:
The t-value for a 80% confidence interval and 24 degrees of freedom is t=1.318.
The margin of error (MOE) can be calculated as:
Then, the lower and upper bounds of the confidence interval are:
The 80% confidence interval for the population mean nitrate concentration is (0.144, 0.186).
Answer:
4 or 8
Step-by-step explanation:
Hey there! :)
For this, you have to use the Pythagorean Theorem.
a² + b² = c² is the same as c² - a² = b²
c = 26
26² = 26 × 26 = 676
a = 10
10² = 10 × 10 = 100
676 - 100 = 576
√576 = 24
b = 24 cm
Hope this helps :)
Answer:
Step-by-step explanation:
Well, a rational number is like anything like -2,-1,0,1,2, etc. Also that includes perfect squares like 16 or 36, and repeating decimals that either don't continue into infinity or repeat, like, 5.2, or 2.14141414...
Step-by-step explanation:
If a+b=50
When b=30
a=50-b
a= 50 - 30
a=20
Therefore 20(a)+30(b)=50