Answer:
the last one
Step-by-step explanation:
Answer:
2.28% of tests has scores over 90.
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:
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:
What proportion of tests has scores over 90?
This proportion is 1 subtracted by the pvalue of Z when X = 90. So
has a pvalue of 0.9772.
So 1-0.9772 = 0.0228 = 2.28% of tests has scores over 90.
<h3>
Answer: 112</h3>
=========================================================
Explanation:
The angle adjacent to the 146 degree angle is 180-146 = 34 degrees.
In other words, the angles 34 and 146 combine to 180. These angles are supplementary.
The tickmarks on this triangle tell us it is isosceles. The angles opposite the congruent sides are congruent angles. So the unmarked interior angles (not marked x) are 34 degrees each.
Now use the fact that any triangle has its interior angles always add to 180
x+34+34 = 180
x+68 = 180
x = 180-68
x = 112
Answer:
Below
Step-by-step explanation:
sin(2x) = 2 ×cos(x)× sin(x)
● sin(x) = 2 × cos(x) × sin(x)
● 2 × cos(x) = 1
● cos (x) = 1/2
So we can deduce that:
● x = Pi/3 + 2*k*Pi
● or x = -Pi/3 + 2*k*Pi
K is an integer
<span>The urn contains 2 purple balls and 4 white balls. The player pay $4 for start the game and get $1.5 for every ball drawn until one purple ball is drawn. The maximal revenue would be $7.5 when 4 white balls and 1 purple balls are drawn.
If the purple ball is p and white ball is w, t</span>he possible sample space of drawings are {p, wp, wwp, wwwp, wwwwp}
<span>1. Write down the probability distribution for the player earning
The player earning </span>for each event depends on the number of balls drawn subtracted the ticket price.<span>
p= 2/6
The player earnings would be: 1*$1.5 -$4= - $2.5
wp= (4*2)/(6*5) = 4/15
</span>The player earnings would be: 2*1.5- $4= - $1
wwp= (4*3*2)/(6*5*4)= 1/5
The player earnings would be: 3*$1.5 -$4= $0.5
wwwp= (4*3*2*2)/(6*5*4*3*2)= 2/15
The player earnings would be: 4*$1.5 -$4= $2
wwwwp= (4*3*2*2*1)/(6*5*4*3*2*1) = 1/15
The player earnings would be: 5*$1.5 -$4= $3.5
2. Find its expected value
The expected value would be:
chance of event * earning
You need to combine the 5 possible outcomes from the number 1 to get the total expected value.
Total expected value= (1/3 * - 2.5)+ (4/15*-1) + (1/5*0.5) + (2/15 *2) + ( 1/15 *3.5)=
(-12.5 -4 + 1.5 + 4 + 3.5) /15= -$7.5
This game basically a rip off.
