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3 years ago

If the average (arithmetic mean) of four different numbers is 30, how many of the numbers are greater than 30 ?

Mathematics

1 answer:

IrinaVladis [17]3 years ago

6 0

Answer:

Maximum 3 numbers. Minimum 1 number.

Step-by-step explanation:

Well, let us look at the case when 3 numbers are greater than 30. Let us take numbers as 1, 2, 3 and 114 and find their mean which is (1+2+3+114)/4=30.

Now let us look at the case in which 2 numbers greater than 30. Let us take numbers 28, 29, 31 and 32 and find their mean which is (28+29+31+32)/4=30.

Now let us look at the case in which 1 number greater than 30. Let us take numbers 27, 28, 29 and 36 and find their mean which is (27+28+29+36)/4=30.

So it can be concluded that maximum 3 numbers and minimum 1 number are greater than 30.

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yan [13]

Answer:

D r and s

Step-by-step explanation:

because they are next to each other in a straight line and never cross one another

3 0

3 years ago

A tree 5 feet tall grows an average of 8 inches each year. Write and graph an equation to model the tree's height h after x year

Stolb23 [73]

Okay my example will be for if you watched that tree for like 5 years and I can`t really put in a graph here so sorry about that

The equation is basically the original height, 5 foot, and multiply it by the number of years you`ve been watching it grow for example when you watch it for 6 years then it will be the original height of 5 foot multiplied by the number years it has been since you look at it which is 6 years. 5 * 6 = 30 so after 6 years it will grow 30 inches.
1st year: 5 foot
2nd year: 5 foot * 2 = 10 inch increase in height
3rd year: 5 foot * 3 = 15 inch increase in height
4th year: 5 foot * 4 = 20 inch increase in height
5th year: 5 foot * 5 = 25 inch increase in height
So basically the equation is 5 foot * the number of years its been = total increase in height

I hope this helps

3 0

4 years ago

The rate at which a plant grows is constant. At the 3rd week it is 12 inches tall and at the 5th week it is 20 inches tall. If t

Arada [10]

First, you want to find the slope of the line. You do this by taking the difference in the heights divided by the difference of the time.
m=(20-12)/(5-3)
m=8/2
m=4
Now plug the information into slope intercept form (you can choose whichever set of data you want, just as long as you are consistent):
y=mx+b
12=(4)(3)+b
12=12+b
b=0
This is saying that there is no y-intercept (b).
So our final equation is:
y=4x
The question is asking for y when x is 1, so just plug it into the equation:
y=4(1)
y=4

Hope this helps!

7 0

3 years ago

Read 2 more answers

Mod 8 Honors Assignment - Sequences and Series

Gekata [30.6K]

The numbers in the sequence will be 40, 80, and 160.

<h3>How to get the values?</h3>

Let x be the first number in the sequence, so the first three numbers are {x, 0.5x, 0.5²x}.

Then

{x/4 + 10, 0.5x - 10, 2(0.5²x) + 10}

0.5x - 10 = x/4 + 10 + c = x/2 - 10 = x/4 + 10 + c

2(0.5²x) + 10 = 0.5x - 10 + c = x/2 + 10 = x/2 - 10 + c

Solve the second equation for c :

x/2 + 10 = x/2 - 10 + c

c = 20

Substitute this into the first equation and solve for x :

x/2 - 10 = x/4 + 10 + 20

x/4 = 40

x = 160

Then the terms are {160, 80, 40}

Learn more about sequence on:

brainly.com/question/6561461

#SPJ1

4 0

2 years ago

1. 72% of the students in Math 6 at AZVA are currently passing mastering their lessons. If 324 students are currently mastering

Alexeev081 [22]

Answer:

1. a. 72/100 = 324/x

72x = 32,400

b. 450 students are in Math 6

2. a. o = 3b

b. o = 3 pounds

3. a. Most popular animals:

A. Dogs - 67%

B. Cats - 20%

C. Other - 8%

D. None - 4%

E. Horses - 1%

b. 20 students

c. If 75 students have cats, the estimate of 250 students isn't correct.

The actual number of students interviewed is 375.

Step-by-step explanation:

1. a. Let's use the following equation to solve the question:

x = Students that are in Math 6

72/100 = 324/x

72 * x = 324 * 100

72x = 32,400

b. Let's solve the equation, as follows:

x = 32,400/72

x = 450

450 students are in Math 6

2. a. The equation is:

o = 0.15 *20b

o = 3b

where, o = weight of oats in pounds and b = number of dog food bags

b. Let's find out the weight of the oats in one dog food bag, using our equation:

o = 0.15 *20b

o = 0.15 *20 * 1

o = 3 pounds

3. a. Most popular animals:

A. Dogs - 67%

B. Cats - 20%

C. Other - 8%

D. None - 4%

E. Horses - 1%

b. If 250 students were interviewed, the 8% who answered "other" are:

8% of 250 = 0.08 * 250 = 20 students

c. If 75 students have cats, the estimate of 250 students isn't correct.

The 20% of 250 is 50, not 75.

0.2 * 250 = 50

The actual number of students interviewed is:

x = Actual number of students interviewed

75/x = 20/100

20x = 7,500

x = 7,500/20

x = 375

The actual number of students interviewed is 375.

3 0

3 years ago