Step-by-step explanation:
Multiply by the reciprocal, also sometimes referred to as "Keep, Change, Flip." Here is how it works. You rewrite the division question as a multiplication question by flipping the second fraction over. Next, keep the first number, change the division to multiplication and then flip the second fraction over.
Answer:
The minimum score a person must have to qualify for the society is 162.05
Step-by-step explanation:
Problems of normally distributed samples can be solved using the z-score formula.
In a set with mean 
and standard deviation 
, the zscore 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 pvalue, we get the probability that the value of the measure is greater than X.
In this problem, we have that:
Test scores are normally distributed with a mean of 140 and a standard deviation of 15. This means that 
.
What is the minimum score a person must have to qualify for the society?
Since the person must score in the upper 7% of the population, this is the X when Z has a pvalue of 0.93.
This is 
.
So
The minimum score a person must have to qualify for the society is 162.05
Answer:
z = -166
Step-by-step explanation:
1. Subtract 3 from both sides to get z/2 = -83
2. Multiply 2 by both sides to get z = -166
z = -166
Explanation:
The Law of Cosines specifies the relationship between the three sides of a triangle and any one of the angles. If the sides are designated a, b, and c, and the angle opposite side c is C, then it tells you ...
c² = a² + b² -2ab·cos(C)
This relationship can be used to find any and all angles, given the three sides of a triangle. Or, having found one angle using the Law of Cosines, the others can be found using the Law of Sines:
sin(A)/a = sin(B)/b = sin(C)/c
_____
Typically, inverse functions are required. That is, from the Law of Cosines, ...
C = arccos((a² +b² -c²)/(2ab))
And from the Law of Sines, ...
A = arcsin(a/c·sin(C))
B = arcsin(b/c·sin(C))
_____
<em>Note on solving triangles</em>
It often works best to make use of exact values where possible. It is also a good idea to start with the longest side/largest angle. Of course, once you have two angles the other can be found as the supplement of their sum.
