Answer:
-2x + 5y = 25
Step-by-step explanation:
1) area of a cicular pool
area of a circle=πr^2 d=2.5 then r=2.5/2
A=3.14 *(2.5/2)^2
A=4.906m^2 A=4.9m^2
2) arae of a coin
<span>(if i read it right d=15mm?)
</span>A=πr^2 d=15 then r=15/2
A=3.14*(15/2)^2 =176.6mm^2
Rest all are same problems u try to solve it
The dimensions of the pool are 67ft in length and 32 feet in width
Using the t-distribution to build the 99% confidence interval, it is found that:
- The margin of error is of 3.64.
- The 99% confidence interval for the population mean is (19.36, 26.64).
<h3>What is a t-distribution confidence interval?</h3>
The confidence interval is:

In which:
is the sample mean.
- s is the standard deviation for the sample.
The critical value, using a t-distribution calculator, for a two-tailed 95% confidence interval, with 21 - 1 = 20 df, is t = 2.086.
The other parameters are given as follows:

The margin of error is given by:

Hence the bounds of the interval are:


The 99% confidence interval for the population mean is (19.36, 26.64).
More can be learned about the t-distribution at brainly.com/question/16162795
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Answer:
7
Step-by-step explanation:
first, we would set up an equation. let 3x-4 represent "four less than a number tripled". "a number" would be represented by x. let x+10 represent "the same number increased by 10".
set 3x-4 and x+10 equal to each other:
3x-4=x+10
next, we would solve this equation for x. first we would get the x together on one side of the equation. we would do this by subtracting x from both sides to remove it from the right side of the equation:
2x-4=10
then, we would get the 2x by itself. we would do this by adding 4 to both sides:
2x=14
finally, we would divide each side of the equation by 2 to find x:
x=7.
The number is 7.