Step-by-step explanation:
Here Given
Total counters = 81
red counters are 9 more than the yellow ones.
And Yellow counter = blue counter
So let the Yellow counter be x and as blue counter and yellow counter are same then blue counter will be also x
And by the question
Red counter = 9 + x
Now
9 + x + x + x = 81
9 + 3x = 81
3x = 81 - 9
3x = 72
x = 72 / 3
Therefore x = 24
Now
Red counters = 9 + 24 = 33
Blue counters = 24
Yellow counters = 24
Hope it helped :)
The z-score is the number of standard deviations away from the mean. We first subtract the actual score from the mean, then divide the difference by the standard deviation. In this case, our actual score is 13, so we subtract from the mean of 16, then divide by the SD of 2
(13 - 16) / 2 = -1.5
Answer:
the answer is -7
Step-by-step explanation:
hope this helps
Answer: $7.70
Step-by-step explanation:
Given : A box contains eighteen $1 bills, ten $5 bills, eight $10 bills, three $20 bills, and one $100 bill.
Total bills = 
We know that probability of any event =
i.e. the probability of getting $1 bills =
Probability of getting $10 bills =
Probability of getting $5 bills =
Probability of getting $20 bills =
Probability of getting $100 bills =

Hence, the expected value of your draw= $7.70
The probability that a student scored less than 55% on the exam is 0.134%.
<h3>What is a normal distribution?</h3>
It's the probability curve of a continuous distribution that's most likely symmetric around the mean. On the Z curve, at Z=0, the chance is 50-50. A bell-shaped curve is another name for it.
We have:
Mean of the sample = 70
Standard deviation = 5
= P(X<55%)
Z = (55-70)/5
Z = -3
P(X < -3)
From the Z table:
P(x<-3) = 0.0013499
or
P(x<-3) = 0.134%
Thus, the probability that a student scored less than 55% on the exam is 0.134%.
Learn more about the normal distribution here:
brainly.com/question/12421652
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