Answer:
the probability that a sample of the 35 exams will have a mean score of 518 or more is <em> 0.934 </em>or<em> 93.4%</em>.
Step-by-step explanation:
This is s z-test because we have been given a sample that is large (greater than 30) and also a standard deviation. The z-test compares sample results and normal distributions. Therefore, the z-statistic is:
(520 - 518) / (180/√35)
= 0.0657
Therefore, the probability is:
P(X ≥ 0.0657) = 1 - P(X < 0.0657)
where
- X is the value to be standardised
Thus,
P(X ≥ 0.0657) = 1 - (520 - 518) / (180/√35)
= 1 - 0.0657
= 0.934
Therefore, the probability that a sample of the 35 exams will have a mean score of 518 or more is <em>0.934 or 93.4%</em>.
An arc of length 30 m : l = 30 m.
r = 15 m, ∠ A = ?
Formula for the length of an arc is:
l = r π A / 180° ( where A is the central angle )
A = l · 180 / r π = ( 30 · 180 ) / ( 15 · 3.1415926 ) = 114.43 °
This is very close to your result.
Answer:
68 feet
Step-by-step explanation:
A submarine cruised below the surface of the water
During training exercise, each time descending= 45 feet
Number of dives= 4
Total distance he descended= 45×4 feet
Total distance he descended= 180 feet
Then, it rose by= 112 feet
Now , the distance he is at below the surface if water= 180- 112
The distance he is at below the surface if water= 68 feet
Now, he is at 68 feet below the surface of the Earth
Hence, the correct answer is 68 feet
Part 1: 52 degrees Fahrenheit
Part 2: 29 degrees Fahrenheit
