Using the normal distribution, it is found that the cut off score for the top 10% is of 8.4 seconds. It means that a person with a time of 8.4 seconds or lower is in the faster 10% of runners.
In a normal distribution with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the z-score of a measure X is given by:
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
It 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, which is the percentile of X.In this problem:
Mean of 10.2 seconds, hence [tex]\mu = 10.2[/tex]Standard deviation of 1.4 seconds, hence [tex]\sigma = 1.4[/tex].The lower the times, the faster the runners are, hence, the cut off score for the top 10% is the 10th percentile, which is X when Z has a p-value of 0.1, so X when Z = -1.28.
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
[tex]-1.28 = \frac{X - 10.2}{1.4}[/tex]
[tex]X - 10.2 = -1.28(1.4)[/tex]
[tex]X = 8.4[/tex]
The cut off score for the top 10% is of 8.4 seconds. It means that a person with a time of 8.4 seconds or lower is in the faster 10% of runners.
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Out of the 50 students in Mrs. Green's class, 9 have a pet. What percent of the students in Mrs. Green's class have a pet?
The percent of students in Mrs. Green's class that have a pet is_____%
Answer:
4.5% i think reason usually percent is compared in 100% and out of 100 10 means 10 % so 4.5 is the answer
Answer:
18%
Step-by-step explanation:
9÷50×100 = 18%
9 means how many students have pets
50 means how many students are in Mrs. Green's class
18% is how many students that have a pet in Mrs. Greens class
Drawing a Card: If one card is drawn from a deck, find the probability of getting a red 6. Leave your answer in non reduced fraction.
Answer:
Well assuming its playing cards
There are 54 playing cards including jokers.
There are only 2 red 6 cards.
The hearts and the diamonds.
Now so techincially its a 2/54 chance
So 2/54 chance of drawing a red card
Answer:
2/52
Step-by-step explanation:
52 cards in a deck as jokers are not used in professional card places red = 1/2 of 52 = 26/52 drawing red 6 = 1/2 of 4/4 = 2/4 26/52 / 2/52 = 13 which proves 13 cards in each red and 2/52 red 6's in a full deck
What is 96 x 4762 please tell me how to solve this
Answer:
It's 457152.
Step-by-step explanation:
4762
x 96
Lay it out like this. Then begin muliplying the bottom right number (6) by each top number. Then once finished, add a 0 below your answer. Then multiply the bottom left number (9) by each top number again. Once that's all finished, add those two answers.
Chris has a balance of $54 in his account. he earns $9 per hour at the movie theatre. how many hours will he need to work for his balance to be zero?
Answer:
6 hours
Step-by-step explanation:
I assume the balance is on a credit card. He needs to pay off the $54.
He earns $9/hour.
$54/($9/hour) = 6 hours
In 6 hours he earns $54, and he can pay $54 to zero his balance.
Answer: 6 hours
PLEASE HELP ME ILL MARK BRAINLIEST !!!!! spam reported
Answer:
2, 32
Step-by-step explanation:
The question is asking where X could be (what value it could have) to make it 15 away from W, making a line segment of that length if they were to be connected. This can be solved by individually adding and subtracting 15 to/from the value of W: 17. Adding 15 to 17 gives you 32, while subtracting gives you 2, and X could be either of these, so your answer is 2, 32. (It's common to order them in increasing order, but you shouldn't be marked off if you do it in reverse.)
A rectangular room is four times as long as it is wide, and its perimeter is 90 meters. Find the width of the room.
If Betty makes monthly deposits at the end of each month in an account that earns 8% interest compounded monthly,
(a) How much would she have to deposit every month in order to have $40,000 in the account in 9 years? $
(b) Find her total balance in the account at the end of three months. $
(c) Find the total amount of interest that she's earned after the 9 years. $
9514 1404 393
Answer:
(a) $254.08
(b) $767.34
(c) $12,449.36
Step-by-step explanation:
These questions are best answered by a financial calculator or app. Such are available for your phone or tablet. A spreadsheet also has built-in functions for making these calculations.
(a) FV = $40,000, i = 8% per year, n = 9 years (108 months), compounding 12 times per year. The monthly deposit needs to be $254.08.
__
(b) Payment = $254.08, n = 3 months, i = 8%/year, compounding 12 times per year. FV = $767.34.
__
(c) The sum of 108 payments of $254.08 is ...
108 × $254.08 = $27,440.64
The interest earned is enough to bring the account value to $40,000, so is ...
$40,000 -27,440.64 = $12,559.36
_____
Additional comment
The amount $254.08 is rounded down to the nearest cent, so the balance after 9 years will be $39,999.70, which is $0.30 short of $40,000. We used $40,000 as the final account balance, so overestimated the interest by $0.30.
There may be additional small changes in the values if you round interest to the nearest cent each month the way a financial institution would. It is hard to tell in these problems how accurate you're intended to be in your calculations.
Use the drawing tools to form the correct answers on the provided dot plot.
Create a dot plot of the data on the average cruising speeds of Red Eagle's planes.
0.78
0.85
0.85
0.80
0.84
0.83
0.79
0.83
0.81
0.84
0.82
0.82
0.86
0.83
0.84
0.83
0.85
0.85
0.81
0.80
0.82
0.84
0.83
0.82
0.87
0.85
0.84
0.81
0.82
0.86
Drawing Tools
Delete Undo
Reset
Select
• Point
0.78
0.80
0.86
0.88
0.82 0.84
Average Cruising Speed
Answer:
hold on
Step-by-step explanation:
do you have options?
So on solving the provided question we can say we can plotting data by x = 0.83; y = 0.79; z = 0.83
Here, we have,
The most typical approach to display data using a chart is a graph that shows the relationship between two additional variables.
Diagrams created by hand or on a computer are also acceptable.
Move 2 units to the right after starting at the origin before going 3 units up.
The coordinates for the points 2, 3, should be shown on the coordinate plane. Clearly state your points.
The pink dot with the letter P thus stands for 2.3.
Before creating a line chart, you need first generate a number line for each value in your data collection.
Put an X (or dot) over each value of the data on the number line after that. For each instance when a value appears in a record, place an X over the corresponding number.
x = 0.83
y = 0.79
z = 0.83
xa = 0.85
ya = 0.85
za = 0.85
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Evaluate
1.50
Enter your answer as a decimal in the box
Answer
3.375
step by step explanation
Answer:
1.5^3
= ( 15 / 10 ) ^ 3
= 3375 / 1000
= 3.375
Explain why the expressions
10 • 16 + 5 and (10 • 16) + 5 are equivalent.
Answer:
These two equations are equivalent because the order of operations states you work from the right to the left and do the multiplication first. Because we do the multiplication first, we get the same answer as the other equation because the parentheses are also done first, meaning these equations both get the same answer.
Step-by-step explanation:
Use graphing technology to find the range of the function f(x)=-x^2+4.f(x)=−x
2
+4.
Answer:
The set of Real numbers
Step-by-step explanation:
x² + 4 is a parabola with the lowest point on the y-axis is 4 and continues up
-x² + 4 is a parabola with the highest point on the y-axis is 4 and continues down.
The range is the distance traveled on the y- axis.
All real numbers.
Math expert please
Factor this completely
Answer:
4(x -4)(2x +1)
Step-by-step explanation:
8x² -16 -28x , rearrange it so the exponents will be going form highest to lowest
8x²-28x -16, factor 4
4(2x² -7x -4),
to get 2x² we need to multiply an x and a 2x
to get -4 we need to multyply 1 and -4 or -1 and 4 or 2 and -2 (can use trial and error method here)
4(x -4)(2x +1)
Check
4(x-4)(2x+1) = (4x -16)(2x+1) = 8x² +4x -32x -16 = 8x²-28x -16
Please please help please please help me please please help please please help me I REALLY NEED HELP PLEASE
Answer:
6789
Step-by-step explanation:
Q7. Ezri can type 600 words in 8 minutes. How many words can she type in 11
minutes?
Answer:
Step-by-step explanation
Did you mean "How long will it take Johnny to TYPE a 2100 word essay?
If so, do the following:
Let x = the number of minutes to type a 2100 word essay
600/8 = 2100/x
600x = 16,800
x = 28 minutes
At a deli counter, there are 9 sandwiches with meat and 10 vegetarian sandwiches. Diane is at the counter buying sandwiches for a picnic. In how many ways
can she choose 9 sandwiches if 7 or more must be vegetarian sandwiches?
Answer:
Step-by-step explanation:
three ways
1) all 9 are veg
2) 8 are veg and 1 has meat
3) 7 are veg and 2 have meat
There are 3 different ways of choosing 9 sandwiches if 7 or more must be vegetarian sandwiches
What is Combination?An arrangement of objects where the order in which the objects are selected does not matter.
Given that at a deli counter, there are 9 sandwiches with meat and 10 vegetarian sandwiches.
9 -Meat sandwiches
10 - veg sandwiches
Diane is at the counter buying sandwiches for a picnic.
we need to find in how many ways can she choose 9 sandwiches if 7 or more must be vegetarian sandwiches
There are 3 different ways of choosing 9 sandwiches.
All 9 are vegetarian sandwiches
8 are vegetarian sandwiches and 1 is meat sandwiches
7 are vegetarian sandwiches and 2 are meat sandwiches
Hence, there are 3 different ways of choosing 9 sandwiches if 7 or more must be vegetarian sandwiches
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Trey runs 3 miles in 25 minutes. At the same rate, how many miles would he run in 20 minutes?
Answer:
Step-by-step explanation:
Set up a proportion.
3/25 = x / 20 Notice that both times are in the denominators. Be sure you always set up a proportion that way. Like units in the denominator. Like units in the numerator.
Cross multiply
3 * 20 = 25 * x Combine
60 = 25x Divide by 25
60/25 = x
x = 2.4 miles in 20 minutes.
Answer:
In 20 minutes, Trey would run 2.4 miles.
Step-by-step explanation:
20x = 25
x = 4/5
This means we multiply the number by 0.8
3 * 0.8 =
3/25 = 2.4/20
2.4 miles / 20 minutes
A. Only Sequence A
B. Only Sequence B
C. Both
D. Neither
Answer:
Only sequence a is your answer
Step-by-step explanation:
Find the geometric mean of 2 and 98. pls explain how to solve this in steps
============================================================
Work Shown:
[tex]m=\text{geometric mean of x and y}\\\\m = \sqrt{x*y}\\\\m = \sqrt{2*98}\\\\m = \sqrt{196}\\\\m = \sqrt{14^2}\\\\m = 14\\\\[/tex]
The geometric mean of two numbers has us do two steps in this order
Multiply the valuesApply the square rootThe geometric mean can be applied to more than two values. Regardless of how many values you have, you always multiply them out. However, the number of values will tell you what kind of root you'll take (eg: 3 values leads to a cube root; 4 values means you'll take a fourth root, etc).
when 3x² - 2x + 1 is subtracted from 2x² +7x + 5, the result will be?
Answer:
-x²+9x+4
Step-by-step explanation:
Hope this helps!
Answer:
-x^2+9x+4
Step-by-step explanation:
2x² +7x + 5
- 3x² - 2x + 1
-x^2+9x+4
Which statement is true about this quadratic equation?
y = 12 – 110 + 7
=
OA.
There is one complex solution.
ОВ.
There is one real solution.
Ос.
There are two complex solutions.
OD.
There are two real solutions.
Answer:
i think B
Step-by-step explanation:
because is right
Answer:
D
Step-by-step explanation:
[tex]y=x^2-11x+7[/tex]
we need to calculate [tex]\Delta = \sqrt{b^2-4ac}[/tex]
and if [tex]\Delta[/tex] is positive we have 2 distinct roots
if [tex]\Delta[/tex] is 0 then we have two identical roots.
If [tex]\Delta[/tex] < 0 then we have two complex solutions.
in this case, [tex]\Delta = \sqrt{11^2-4*7} = \sqrt{121-28}>0[/tex]
the answer is D
What is the slope of the red line
Answer:
1/2
Step-by-step explanation:
Answer:
1/2
Step-by-step explanation:
The price of tickets to the Dakota vs. Chippewa football game goes from $6 to $4, which results in a 50% change in demand for tickets. What is the elasticity? What type of product is it?
If you start at –3 tenths of a unit and then move right 4 tenths of a unit, where do you end up?
Answer:
I don't know what to do with it
A club is participating in a clothing drive. They receive 17 coupons to a pizza place for participating in the drive. For every 60 articles of clothing collected, they will get an additional 11 tickets.
A) Write an equation relating the articles of clothing collected and number of coupons collected using the variables A and C
Answer:
736
Step-by-step explanation:I am dum
\
Based on the chart below if Lucas drives 45 miles per hour in a 20 miles per hour zone, how much should he expect to pay for his ticket?
Answer:
where is the chart? ?????
Abigail has 1 7/8 cups of powdered sugar. She sprinkles 1/2 of the sugar onto a plate of
brownies and sprinkles the rest onto a plate of lemon cookies. How much sugar does Abigail
sprinkle on the brownies?
Kai drives at a speed of 115km/h. Ottawa is 432 from Mississauga. How long should it take for Kai to get to Ottawa?
Show all of your work.
Answer:
3.8 hrs
Step-by-step explanation:
Hello!
All you gotta do is 432/115 which should give 3.8
4/3 x 1/2 = 4/3 ÷ Can you please help me with this? I’d appreciate it.
Answer:
[tex]\mathsf{\frac{4}{3} \:\times\frac{1}{2}\: =\: \frac{4}{3} \:\div\frac{2}{1}}[/tex]
Step-by-step explanation:
The mathematical operation of division is the opposite of multiplication. When you divide two fractions, you will have to take the reciprocal of the divisor, and multiply it with the dividend.
In the given equation, [tex]\mathsf{\frac{4}{3} \:\times\frac{1}{2}\: =\: \frac{4}{3} \:\div\:?}[/tex], we can rewrite this as: [tex]\mathsf{\frac{4}{3} \:\div\:?\:=\:\frac{4}{3} \:\times\frac{1}{2}}[/tex].
As previously mentioned, division is opposite of multiplication. Since the multiplicand in the multiplication of two fractions is ½, then we can assume that the divisor (or the missing fraction) must be the reciprocal of ½, which is [tex]\mathsf{\frac{2}{1}\:or\:2}[/tex].
Therefore, the missing fraction that completes the given mathematical statement is [tex]\mathsf{\frac{2}{1}\:or\:2}[/tex].
[tex]\mathsf{\frac{4}{3} \:\times\frac{1}{2}\: =\: \frac{4}{3} \:\div\frac{2}{1}}[/tex]
What does X equal X=?
The letter "x" is often used in algebra to mean a value that is not yet known. It is called a "variable" or sometimes an "unknown". In x + 2 = 7, x is a variable, but we can work out its value if we try! A variable doesn't have to be "x", it could be "y", "w" or any letter, name or symbol. See: Variable.
There are 200 adults and 300 children at a zoo. The zoo
makes a total of $7000 from the entrance fees, and the
cost for an adult and child to attend is $30. How much
does an adult ticket (x) and child's ticket (y) cost?
Answer: 30
Step-by-step explanation:
200a+300c=7000
a+c=30
