To find a percentage of a number we multiply the percentage times the number and get the result, here we have the percentage and the result and need to find out which number it corresponds to, lets write an equation to do so and keep in mind that the percentage itself can be written in a different way:
225% = 225 out of 100 = 225/100
So we have this equation, where we call x the number we are looking for:
<span>(225%)(x) = 81
</span>(225/100)(x) = 81
so we solve for x:
225x = 81*100 = 8100
x = 8100/225
x = 36
The original number is 36, hence 225% of 36 is 81
We are given with
x1 = 20 min
s1 = 2 min
x2 = 30 min
s2 = 4 min
p = 0.9
Condition (x > 25)
We need to get the t-value between the two means and comparing it wit the t-value for the time of 25 minutes given that there is a 90% probability that the weather will be good. Simply use the t-test formula and use the t-test table to get the probability.
The first equation is

The second equation is

If you sum the two equations you'll cancel y:

And since the sum must be 11, we have y=9.
Answer:
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2
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4
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Step-by-step explanation:
There were no graphs listed in your question. So...
Convert the inequality to interval notation.