Answer:
A) 0.0107
Step-by-step explanation:
Normal Probability Distribution:
Problems of normal distributions can be solved using the z-score formula.
In a set with mean 
and standard deviation 
, the z-score of a measure X is given by:
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 p-value, we get the probability that the value of the measure is greater than X.
Mean of 440 seconds and a standard deviation of 40 seconds.
This means that 
Find the probability that a randomly selected boy in secondary school can run the mile in less than 348 seconds.
This is the p-value of Z when X = 348. So
has a p-value of 0.0107, and thus, the correct answer is given by option A.
Answer:
-9/2
Step-by-step explanation:
-2x-5 = 4
+5 +5
-2x = 9
------ ------
-2 -2
x = -9/2
Answer:
Step-by-step explanation:
The Exponential Product rule tells us that...
Therefore, 
.
Therefore,
Answer:
Because the airline allows each suitcase to hold up to 50 pounds, and it doesn't force them to hold exactly 50 pounds
Equation of an ellipse
→having center (0,0) , vertex (
and covertex 
and focus 
is given by:
As definition of an ellipse is that locus of all the points in a plane such that it's distance from two fixed points called focii remains constant.
Consider two points (a,0) and (-a,0) on Horizontal axis of an ellipse:
Distance from (a,0) to (c,0) is = a-c = 
Distance from (-a,0) to (c,0) is = a + c = 
a -c + a +c
= a + a
= 2 a →(Option A )
