Answer:
a) 0.033
b) 0.468
c) 100
Step-by-step explanation:
We are given the following information in the question:
Mean, μ = 105.3
Standard Deviation, σ = 8
The amount x of miraculin produced (measured in micro-grams per gram of fresh weight) had a normal distribution.
Formula:
![z_{score} = \displaystyle\frac{x-\mu}{\sigma}](https://tex.z-dn.net/?f=z_%7Bscore%7D%20%3D%20%5Cdisplaystyle%5Cfrac%7Bx-%5Cmu%7D%7B%5Csigma%7D)
a) P(x > 120)
![P( x > 120) = P( z > \displaystyle\frac{120 - 105.3}{8}) = P(z > 1.8375)](https://tex.z-dn.net/?f=P%28%20x%20%3E%20120%29%20%3D%20P%28%20z%20%3E%20%5Cdisplaystyle%5Cfrac%7B120%20-%20105.3%7D%7B8%7D%29%20%3D%20P%28z%20%3E%201.8375%29)
![= 1 - P(z \leq 1.8375)](https://tex.z-dn.net/?f=%3D%201%20-%20P%28z%20%5Cleq%201.8375%29)
Calculation the value from standard normal z table, we have,
![P(x > 120) = 1 - 0.967 = 0.033 = 3.3\%](https://tex.z-dn.net/?f=P%28x%20%3E%20120%29%20%3D%201%20-%200.967%20%3D%200.033%20%3D%203.3%5C%25)
b) P(x between 100 and 110)
![P(100 \leq x \leq 110) = P(\displaystyle\frac{100 - 105.3}{8} \leq z \leq \displaystyle\frac{110-105.3}{8}) = P(-0.6625 \leq z \leq 0.5875)\\\\= P(z \leq 0.5875) - P(z \leq -0.6625)\\= 0.722 - 0.254 = 0.468 = 46.8\%](https://tex.z-dn.net/?f=P%28100%20%5Cleq%20x%20%5Cleq%20110%29%20%3D%20P%28%5Cdisplaystyle%5Cfrac%7B100%20-%20105.3%7D%7B8%7D%20%5Cleq%20z%20%5Cleq%20%5Cdisplaystyle%5Cfrac%7B110-105.3%7D%7B8%7D%29%20%3D%20P%28-0.6625%20%5Cleq%20z%20%5Cleq%200.5875%29%5C%5C%5C%5C%3D%20P%28z%20%5Cleq%200.5875%29%20-%20P%28z%20%5Cleq%20-0.6625%29%5C%5C%3D%200.722%20-%200.254%20%3D%200.468%20%3D%2046.8%5C%25)
![P(100 \leq x \leq 110) = 46.8\%](https://tex.z-dn.net/?f=P%28100%20%5Cleq%20x%20%5Cleq%20110%29%20%3D%2046.8%5C%25)
c) P(x < a) = 0.25
![P( x \leq a) = P( z \leq \displaystyle\frac{a - 105.3}{8}) = 0.25](https://tex.z-dn.net/?f=P%28%20x%20%5Cleq%20a%29%20%3D%20P%28%20z%20%5Cleq%20%5Cdisplaystyle%5Cfrac%7Ba%20-%20105.3%7D%7B8%7D%29%20%3D%200.25)
Calculation the value from standard normal z table, we have,
![P( z \leq -0.674) = 0.25](https://tex.z-dn.net/?f=P%28%20z%20%5Cleq%20-0.674%29%20%3D%200.25)
![\displaystyle\frac{x - 105.3}{8} = -0.674\\\\x = -0.674\times 8 + 105.3 = 99.908 \approx 100](https://tex.z-dn.net/?f=%5Cdisplaystyle%5Cfrac%7Bx%20-%20105.3%7D%7B8%7D%20%3D%20-0.674%5C%5C%5C%5Cx%20%3D%20-0.674%5Ctimes%208%20%2B%20105.3%20%3D%2099.908%20%5Capprox%20100)
Answer: 35
Step-by-step explanation:
Triangle BDC is an equilateral triangle
Triangle ABD is an isosceles triangle
so the length of BD is 8
because BDC is equilateral all sides are 8
then you add your numbers up
8+8+8+11
=35
Answer:
The correct option is (d). 2.15 meters.
Step-by-step explanation:
According to the given scenario, the approximate length of an alligator at the 67th percentile is as follows:
The length of an alligator is
.
Let us assume the
be the 67th percentile
![P(X](https://tex.z-dn.net/?f=P%28X%20%3CP67%29%20%3D%200.67%5C%5C%5C%5CP%28Z%20%3C%20%5Cfrac%7BP_%7B67%20-%202%20%7D%7D%7B0.35%7D%20%29%20%3D%200.67%5C%5C%5C%5C%5Cemptyset%20%28%5Cfrac%7BP_%7B67%20-%202%20%7D%7D%7B0.35%7D%20%29%20%3D%200.67%5C%5C%5C%5C%20%28%5Cfrac%7BP_%7B67%20-%202%20%7D%7D%7B0.35%7D%20%29%20%3D%20%5Cemptyset%5E%7B-1%20%280.67%29%5C%5C%5C%5C)
![\frac{P_{67 - 2 }}{0.35} = 0.44\\\\P_{67} = 2.154](https://tex.z-dn.net/?f=%5Cfrac%7BP_%7B67%20-%202%20%7D%7D%7B0.35%7D%20%3D%200.44%5C%5C%5C%5CP_%7B67%7D%20%3D%202.154)
Hence, the correct option is (d). 2.15 meters