Answer:
The z-distribution should be used for this problem.
Step-by-step explanation:
The population distribution is assumed to be normal. Which distribution to use?
If we have the standard deviation for the sample, we use the t-distribution.
If we use the standard deviation for the population, we use the z-distribution.
There is a known standard deviation of 2.2 minutes.
This means that 2.2 is the population standard deviation, and thus, the z-distribution should be used for this problem.
<h3>
Answer: 9</h3>
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Work Shown:
a = unknown = leg #1
b = 12 = leg #2
c = 15 = hypotenuse
Plug those values into the pythagorean theorem and solve for 'a'
a^2 + b^2 = c^2
a^2 + (12)^2 = (15)^2 .... substitution
a^2 + 144 = 225
a^2 = 225 - 144 ... subtracting 144 from both sides
a^2 = 81
a = sqrt(81) .... applying square root to both sides
a = 9
Answer:
-16
Step-by-step explanation:
5^2+7/5-7
32/-2
-16
30% of £10 = £3
30% discount = £10 - £3 = £7
Cake costs £7
