1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
faust18 [17]
2 years ago
13

1)A student earned a grade of 80% on a math test that had 60 problems. How many

Mathematics
2 answers:
mash [69]2 years ago
8 0

Answer: 48

Step-by-step explanation:

80% of 60 or 80/100 x 60 = 48

FrozenT [24]2 years ago
7 0

Answer:

48

Step-by-step explanation:

80% = .8

60 x .8 = 48

You might be interested in
Please answer quickly thanks :)
Bezzdna [24]

b< 11: The board is shorter than 11 cm

b > 11: The box contains more than 11 books

b < 12: There are fewer than 12 beetles in a jar.

b > 12: The building is taller than 12 ft

5 0
2 years ago
The sales tax rate is 8.2%. Estimate the sales tax on a computer that costs $550.
Butoxors [25]
Asking the Math Gods...

550*.082+550=$595.10

$45.10 in tax

7 0
3 years ago
Read 2 more answers
Espano
nikitadnepr [17]

Answer:

The time at which the two trains will meet is 1 hour and 24 minutes

Step-by-step explanation:

The distances between the two trains = 196 miles

The direction of the two trains = Towards each other

The speed of one of the trains = 80 miles per hour

The speed of the other train = 60 miles per hour

Let 't' represent the time at which the two trains meet, we have;

80·t + 60·t = 196

∴ 140·t = 196

t = 196/140 = 7/5

The time at which the two trains will meet, t = 7/5 hours = 1.4 hours = 1 hour, 24 minutes.

3 0
3 years ago
It is known that the life of a particular auto transmission follows a normal distribution with mean 72,000 miles and standard de
scoray [572]

Answer:

a) P(X

P(z

b) P(X>65000)=P(\frac{X-\mu}{\sigma}>\frac{65000-\mu}{\sigma})=P(Z>\frac{65000-72000}{12000})=P(z>-0.583)

P(z>-0.583)=1-P(Z

c) P(X>100000)=P(\frac{X-\mu}{\sigma}>\frac{100000-\mu}{\sigma})=P(Z>\frac{100000-72000}{12000})=P(z>2.33)

P(z>2.33)=1-P(Z

Sicne this probability just represent 1% of the data we can consider this value as unusual.

d) z=1.28

And if we solve for a we got

a=72000 +1.28*12000=87360

So the value of height that separates the bottom 90% of data from the top 10% is 87360.  

Step-by-step explanation:

Previous concepts

Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".

The Z-score is "a numerical measurement used in statistics of a value's relationship to the mean (average) of a group of values, measured in terms of standard deviations from the mean".  

Part a

Let X the random variable that represent the life of a particular auto transmission of a population, and for this case we know the distribution for X is given by:

X \sim N(72000,12000)  

Where \mu=72000 and \sigma=12000

We are interested on this probability

P(X

And the best way to solve this problem is using the normal standard distribution and the z score given by:

z=\frac{x-\mu}{\sigma}

If we apply this formula to our probability we got this:

P(X

And we can find this probability using excel or the normal standard table and we got:

P(z

Part b

P(X>65000)

And the best way to solve this problem is using the normal standard distribution and the z score given by:

z=\frac{x-\mu}{\sigma}

If we apply this formula to our probability we got this:

P(X>65000)=P(\frac{X-\mu}{\sigma}>\frac{65000-\mu}{\sigma})=P(Z>\frac{65000-72000}{12000})=P(z>-0.583)

And we can find this probability using the complement rule and excel or the normal standard table and we got:

P(z>-0.583)=1-P(Z

Part c

P(X>100000)

And the best way to solve this problem is using the normal standard distribution and the z score given by:

z=\frac{x-\mu}{\sigma}

If we apply this formula to our probability we got this:

P(X>100000)=P(\frac{X-\mu}{\sigma}>\frac{100000-\mu}{\sigma})=P(Z>\frac{100000-72000}{12000})=P(z>2.33)

And we can find this probability using the complement rule and excel or the normal standard table and we got:

P(z>2.33)=1-P(Z

Sicne this probability just represent 1% of the data we can consider this value as unusual.

Part d

For this part we want to find a value a, such that we satisfy this condition:

P(X>a)=0.1   (a)

P(X   (b)

Both conditions are equivalent on this case. We can use the z score again in order to find the value a.  

As we can see on the figure attached the z value that satisfy the condition with 0.9 of the area on the left and 0.1 of the area on the right it's z=1.28. On this case P(Z<1.28)=0.9 and P(z>1.28)=0.1

If we use condition (b) from previous we have this:

P(X  

P(z

But we know which value of z satisfy the previous equation so then we can do this:

z=1.28

And if we solve for a we got

a=72000 +1.28*12000=87360

So the value of height that separates the bottom 90% of data from the top 10% is 87360.  

5 0
3 years ago
The side lengths of a triangle are 5,3,and 4. Is this a right triangle
Serggg [28]

Answer:

Yes

Step-by-step explanation:

3, 4, 5 is a pythagorean triplet, meaning they satisfy the Pythagorean theorem.

7 0
3 years ago
Other questions:
  • Fill in each box with the correct numb<br> 5(X+9)=5. +5.
    11·1 answer
  • Considered two events such that P(A)=3/5, P(B)=2/3, and P(AnB)=1/5. Are the events A and B independent events?
    6·1 answer
  • 3x-5y=9whats the answer
    7·1 answer
  • Considers a problem in the estimation of linkages in genetics. McLachlan and Krishnan (1997) also discuss this problem and we pr
    9·1 answer
  • Marina's New Year's resolution is to ride her bike 5000 miles.
    11·1 answer
  • Somebody help me please
    12·1 answer
  • Please help!! Find x, A, B, and C
    14·1 answer
  • A map of a park has a scalar of 1 inch to 1,000 feet. Another map of the same park has a scale of 1 inch to 500 feet. Which map
    11·1 answer
  • PLEASE HELP!! ILL GIVE BRAINLIEST!!
    12·1 answer
  • What is the equation of the line that passes
    13·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!