Answer:
And the mean would be:
And the standard deviation of total time would be:
Step-by-step explanation:
Previous concepts
Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".
The Z-score is "a numerical measurement used in statistics of a value's relationship to the mean (average) of a group of values, measured in terms of standard deviations from the mean".
Solution to the problem
Let total life time of t four transistors T = X1 + X2 + X3 + X4 (where X1,X2,X3 and X4 are life time of individual transistors
For this case the mean length of time that four transistors will last
And the mean would be:
And the standard deviation of total time would be:
Answer:
Option 3.
Step-by-step explanation:
Angle E and angle A are corresponding angles, therefore they are congruent angles. Corresponding angles have the same angle.
Answer:
Collin mistake is step 1
correct answer 
Step-by-step explanation:
Answer:
3.41 feet
Step-by-step explanation:
Area = Length × Breath
Area of the rectangular lawn = 100 × 50
= 5000 feet²
The sidewalk must occupy an area no more than 10% of the total lawn area.
So, the area of the sidewalk would be not more than = 10% × 5000
= 0.10 × 5000
= 500 feet²
Let the width of the sidewalk = x feet
area of the side walk = (L×W of the long way) + ((L-x)×W of the short way)
(100 × x) + ((50 - x) × x) < 500
100x + (50-x)(x) < 500
-x² + 150x < 500
-x² + 150x = 500
-x² + 150x - 500 = 0
By using quadratic formula
or 
x = 3.41089 ≈ 3.41 feet or x = 146.58
Therefore, width of the sidewalk would be 3.41 feet.
Her total allowance as a fraction could be expressed by 9/9. When you subtract the amount that she used, 4/9, you are left with 5/9, which is the solution.
