Answer:
9.18% probability the miners find more than 16 ounces of gold in the next 1000 tons of dirt excavated
Step-by-step explanation:
Problems of normally distributed samples are solved using the z-score formula.
In a set with mean
and standard deviation
, the zscore of a measure X is given by:
![Z = \frac{X - \mu}{\sigma}](https://tex.z-dn.net/?f=Z%20%3D%20%5Cfrac%7BX%20-%20%5Cmu%7D%7B%5Csigma%7D)
The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.
In this problem, we have that:
![\mu = 12, \sigma = 3](https://tex.z-dn.net/?f=%5Cmu%20%3D%2012%2C%20%5Csigma%20%3D%203)
What is the probability the miners find more than 16 ounces of gold in the next 1000 tons of dirt excavated?
This is 1 subtracted by the pvalue of Z when X = 16. So
![Z = \frac{X - \mu}{\sigma}](https://tex.z-dn.net/?f=Z%20%3D%20%5Cfrac%7BX%20-%20%5Cmu%7D%7B%5Csigma%7D)
![Z = \frac{16 - 12}{3}](https://tex.z-dn.net/?f=Z%20%3D%20%5Cfrac%7B16%20-%2012%7D%7B3%7D)
![Z = 1.33](https://tex.z-dn.net/?f=Z%20%3D%201.33)
has a pvalue of 0.9082
1 - 0.9082 = 0.0918
9.18% probability the miners find more than 16 ounces of gold in the next 1000 tons of dirt excavated
Answer:
therefore = 8: 20 a.m
Step-by-step explanation:
The time will they back at the bus depot together is shown below:
The factors of 20 minutes and 35 minutes are 5, 4 and 5, 7
So here the LCM is 5
Now
= 5 × 4 × 7
= 140 mins later
As the bus took off at 6 am
So,
Hours Mins
6 0
+ 2 20 (140 mins = 2 hrs 20 mins)
= 8 20
therefore = 8: 20 a.m
Step-by-step explanation:
step 1. break up the shape into 2 triangles and one rectangle
step 2. A = area of triangle 1 (t1) + area of triangle 2 (t2) + area of the rectangle (r)
step 3. t1 = (1/2)bh where b is the base and h is the height. definition of the area of a triangle.
step 4. t1 = (1/2)(3)(2) = 3ft^2.
step 5. t2 = (1/2)(3)(3) = 4.5ft^2.
step 6. r = bh where b is the base and h is the height. definition of the area of a rectangle.
step 7. r = bh = (8)(4) = 32ft^2.
step 8. A = t1 + t2 + r = 3 + 4.5 + 32 = 39.5ft^2.
Answer: (c) 31 (d) 30 (e) 41 (f) 10
<u>Step-by-step explanation:</u>
NOTES about angles of a rhombus:
- diagonals are angle bisectors (cut the angle into 2 equal parts)
- diagonals are perpendicular to each other (90°)
- two adjacent triangles of a rhombus form an isosceles triangle
(c) Given: ∠CBD = 59°
Per rule 2 → ∠BEC = 90°
Triangle Sum Theorem: sum of the angles of a triangle = 180°
∠CBD + ∠BEC + ∠BCE = 180°
59° + 90° + ∠BCE = 180°
149° + ∠BCE = 180°
∠BCE = 31°
(d) Given: ∠BCD = 120°
Per rule 3 → ∠CBD = ∠CDB
Triangle Sum Theorem: sum of the angles of a triangle = 180°
∠CBD + ∠CDB + ∠BCD = 180°
2∠CBD + 120° = 180°
2∠CBD = 60°
∠CBD = 30°
(e) Given: ∠AED = 2x+8
Per rule 2 → ∠AED = 90°
2x+8 = 90
2x = 82
x = 41
(f) Given: ∠BCE = 3x + 3 and ∠ECD = 5x - 17
Per rule 1 → ∠BCE = ∠ECD
3x + 3 = 5x- 17
3 = 2x - 17
20 = 2x
10 = x
The answer is c -2. That’s honestly too easy