Hello there! :-)
The formula for finding the area of a circle is
[tex]A=\pi r^{2}[/tex]Notice that only the radius is squared.
We are given the radius of the circle: 21 cm.
We plug the value of r into the formula:
A=π(21)²A=π(441)A=1,385 cmHope this helps. Use the comment section to clarify your doubts.
Answered by
~A teen whose hobby is helping people with their homework
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Good luck.
Answer:
A=1.386 cm²
Step-by-step explanation:
[tex]\sf\bf A = \pi \times r \times r[/tex]
[tex]\sf\bf = \frac{22}{7} \times 21 \times 21[/tex]
[tex]\sf\bf = \frac{22}{\cancel{7}} \times \cancel{21} \times 21[/tex]
[tex]\sf\bf = 22 \times 3 \times 21[/tex]
[tex]\sf\bf = 66 \times 21[/tex]
[tex]\sf\bf = 1.386 \: {cm}^{2}[/tex]
A student received scores of 85 and 78 on the first two exams. All exams have a maximum score of 100. What are the possible scores the student could receive on the third exam so that the average of the three exams is at least 80Write your answer in interval notation
Based on the information given, the student should score at least 77 in the last exam.
Since the student wants to get an average of at least 80. Therefore, the total scores should be:
= 80 × 3 = 240
The student received scores of 85 and 78 on the first two exams. The addition of this will be:
= 85 + 78 = 163
Therefore, his score in the last exam should be:
= 240 - 163
= 77
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A colony of bacteria is growing at a rate of 50% per hour. If this rate of growth remains the same and the colony starts with 100 bacteria, approximately how many bacteria will there be after 6 hours
Answer:
1,139.0625
Step-by-step explanation:)
100 BACTERIA to start
1Hour = 50% of the start (which is 100 so half would be 50) this suggest 100+50= 150
2hour = 50% of 150 which is 75 and this suggest
150+75= 225
3 hour = 50% of 225 which is 112.5 this suggest
225+112.5=337.5
4hours = 50% of 337.5 which is 168.75 this suggest
337.5 + 168.75=506.25
5hours = 50% of 506.25 which is 253.125 this suggest
506.25+253.125=759.375
6hours = 50% of 759.375 which is 379.6875 this suggest
759.375+379.6875=1,139.0625
Answer: 1139 bacteria
16 #5) Describe the error in finding the value of x.
2-6² +4 2
please help it's review for my finals
Answer: I don’t know :(
Step-by-step explanation:
Answer:
8
Have an amazing day!
I dont know if question 80 is right but i need help on question 79 and 80
Answer:
not sure about 80 but for 79, the answer is -185
Step-by-step explanation:
P(4)= (4)^3 - 4(4)^2 + 3(4) - 5
P(4)= 64 - 16^2 + 12 - 5
P(4)= 64 - 256 + 12 - 5
P(4)= -185
(sorry if i made a mistake)
A rectangular garden is 35m long and 25m broad. find the perimeter of the rectangular garden. find the length of wire required to fence with 2 round.
Answer:
The perimeter is the distance all round,
Step-by-step explanation:
perimeter of a rectangle is gotten by the formula
P=2(L+W)
2(35+25)=120m
The wire covers the distance all round
so we use 120m×2=240m
Please help me I don’t want to fail
Answer:
c
Step-by-step explanation:
Who invent natural numbers???
Answer:
nobody
Step-by-step explanation:
Humans have made use of natural numbers as long as humans have been around. Counting numbers are wired into our consciousness, as they are for many living things.
Research has demonstrated some plants can count up to 5 (generally, carnivorous ones). Honeybees have long been known to be able to count to 4, and recent research shows they can count higher. Fish can count; birds can count; as can many other species.
For most, it takes concentration and/or training to count beyond 4. We are born with an understanding of 1, 2, 3, more.
Nobody "invented" natural numbers.
_____
Additional comment
Prey species survive by being able to count predators. Some predators take advantage of the limitations of number recognition by hunting in groups larger than can be readily counted.
Find the missing value.
Answer:
It would be +3
Step-by-step explanation:
When you add -8 plus a positive 3 that would be a negative -3
Answer:
-5=-8--3
= -3 Start at -8 go down untill u reach -5 then count how many u went down
Given mſn, find the value of x.
(6x+10)
>
(10x+10)
9. The length of a rectangle is 3 cm longer than twice the width. If the area of the rectangle is 65 cm2,
find its length and the width.
Answer:
length: 13 cm
width: 5 cm
Step-by-step explanation:
You may be aware that 65 = 5×13. We note that 13 is 3 more than twice 5, so these are the dimensions of the rectangle:
5 cm wide; 13 cm long
__
If you want so solve this algebraically, you can let w represent the width. Then the length is 2w+3 and the area is ...
A = LW
65 = (2w+3)(w)
In standard form, this equation is ...
2w^2 +3w -65 = 0
To factor this, you look for factors of 2×(-65) = -130 that have a sum of 3. Those would be ...
-130 = (-10)(13)
Then the factored equation is ...
2w^2 +13w -10w -65 = 0
w(2w+13) -5(2w+13) = 0
(w -5)(2w +13) = 0 ⇒ w = 5, -13/2
The positive solution makes sense in this problem, so ...
width = 5 cm
length = 2(5) +3 = 13 cm
What is the length of XY?
Answer:
XY = 11.25
Step-by-step explanation:
Corresponding sides of similar triangles are proportional.
XY/5 = 18/8
XY = 5(9/4) = 45/4
XY = 11.25
Approximately what portion of the box is shaded blue?
Answer:
[tex]\huge\purple{\overline{\quad\quad\quad\quad\quad\quad\quad\quad\quad \ \ \ }}[/tex]
Answer: 1/2
A bag of marbles has 5 blue marbles, 3 red marbles, and 6 yellow marbles. A marble is drawn from the bag at random. How many possible outcomes are there? O 3 0 5 O 6 O 14
Answer:
I think it would be 14 I hope it is right and it helps
2. What conclusion can you make from each pair of true statements? State which law
logic you used.
a. If an animal is an omnivore, then it eats both plants and animals. Orangutans are omnivo
b. If an animal is a female mammal, then it produces milk. If an animal produces milk, it
nurse its young.
mammary gland
c. If a species is endangered, then it is likely to become extinct. Giant panda bears are
endangered
Answer:
tried my best!!!!!
Step-by-step explanation:
a) they eat both meat and palnts
b) it nurses its young,and feeds us beings
c) yes it is
A skydiver's speed during a free fall
reaches 165 feet per second. What is the
speed in meters per second? At this
speed, how many meters will the
skydiver fall during 4 seconds after the
jump? Assume that 1 meter is equal to
3.3 feet.
Answer:
Below in bold.
Step-by-step explanation:
1. 165/3.3 = 50 meters/second.
2. In 4 seconds the skydiver will fall 4*50 = 200 meters.
It costs a man 75 dollars to buy the things that he needs to make hot dogs. The city allows him to sell his hot dog somewhere near the city hall. However, the city hall charges him 1 dollar for each hot dog sold
Calculate how many hotdogs he will have to sell in order to make a profit if the price he charges for 1 hot dog is $1.50.
Find the perimeter of a regular polygon with an interior angle of 90° and side length 3.5 ft.
Please be accurate and explain.
Answer:
p=14 ft
Step-by-step explanation:
The figure that meets these conditions is the square
The perimeter:
4(3.5) = 14 ft.
Hope this helps
Stacy is selling tickets to the school play. The tickets are $7 for adults and $4 for children she sells twice as many adult tickets as children’s tickets and brings in a total of $270. How many of each kind of ticket did she sell?
Stacy sold 15 children tickets and 30 adult tickets.
The tickets are $7 for adults and $4 for children.
She sells twice as many adult tickets as children tickets and bring in a total of $270.
Therefore,
let
number of children ticket sold = x
number of adult ticket sold = 2x
7(2x) + 4(x) = 270
14x + 4x = 270
18x = 270
x = 270 / 18
x = 15
The number of children ticket sold = 15
The number of adult ticket sold = 15 × 2 = 30
learn more about algebra here: https://brainly.com/question/14569336?referrer=searchResults
Help help help help help math math math
Answer:
∠4 = 135°
Step-by-step explanation:
∠4 = the sum of the two remote angles in the triangle. (remote angles are the angles not next to ∠4
∠4 = 80° + 55°
∠4 = 135°
Answer:
<4 = 135
Step-by-step explanation:
I took this test
Find the side of a rhombus if its diagonals are 14 and 48
(Use Pythagorean theorem)
Answer:
25
Step-by-step explanation:
Let,
Rhombus = ABCD
Diagonal = AC and BD
Mark its centre as O
Now,
AC = 2AO
AO = AC/2
AO = 48/2
AO = 24 cm
Also,
BD = 2BO
BO = BD/2
BO = 14/2
BO = 7 cm²
Now,
In ∆AOB
AB² = AO² + BO²
Here, AB is the side
AB² = (24)² + (7)²
AB² = 576 + 49
AB² = 625
AB = √(625)
AB = 25
The students in Class A and Class B were asked how many pets they each have. The dot plots below show the
results
Students in Class A
Number of Pets
Students in Class B
What is the difference between the ranges in the dot plot
Answer:
The answer is 2
Step-by-step explanation:
The range of class A is 5-0 = 5
The range of class B is 3-0 = 3
the difference between 3 and 5 is 2.
A submarine descends 45 1/2 feet from the ocean surface , climbs 30 feet ,and then descends an additional 18 3/4 feet. What must the submarine do now to reach the ocean surface?
A. Descends 94 1/4 feet
B. Climb 94 1/4 feet
C Descends 34 1/4 feet
D.Climbs 34 1/4 feet
Answer:
D.Climbs 34 1/4 feet
Step-by-step explanation:
-45.5 + 30 - 18.75 + h = 0
h = 34.25
How do you do the work on this problem I’ve been stuck in it for a couple hours now.
56.2 m
Step-by-step explanation:
We can solve for the maximum height by calculating the derivative of y with respect to time and then equating it to zero, i.e.,
[tex]\dfrac{dy}{dt} = 0[/tex]
then solve for the time t that satisfies the equation above. The expression for the height y is
[tex]y = 60t - 16t^2[/tex]
Taking the derivative of this expression, we get
[tex]\dfrac{dy}{dt} = 60 - 32t = 0 \Rightarrow t = \dfrac{60}{32} = 1.9\:\text{s}[/tex]
This means that at t = 1.9 s, the ball would have reached its maximum height. To determine this height, use this value for t in the the equation for y to get
[tex]y = 60(1.9\:\text{s}) - 16(1.9\:\text{s})^2 = 56.2\:\text{m}[/tex]
1. What kind of interest does credit card P illustrate?
Answer:
Interest rates can come in all sizes, but for credit cards they generally fall into one of three categories:
variable rate, fixed rate and promotional rate. Most companies issue cards tied to revolving credit. Users of these cards are allowed to carry a balance on their accounts at the end of every billing cycle.Step-by-step explanation:
Hope this helps you !!A pet shop sells mice, rats and gerbils. The ratio of mice to rats is 4:3 and the ratio of mice to gerbils is 7:4. If there are 32 gerbils in stock at present, how many rats are there? Please could you explain your working out.
Answer:
42 rats.
Step-by-step explanation:
since the ratio of mice to gerbils is 7:4, given that there are 32 gerbils, that means 32/4=8 gerbils; in other words, 56mice:32gerbils. Then, to find the # of rats, the ratio is 4:3, so you take the previous value of the # of mice and divide it by 4 to get 14(3)= 42
To understand this question, we need to know what it's asking and what's important and what is not important. Many people skip this step, but it is very important.
It is asking us to Find how many Rats there are.
This problem is defiantly reduced to the simplistic ratio
The next step is to Find clues
The clues are 32 Gerbils, 7:4 and 4:3
Now i like to make a chart but you may skip this step if you want
Gerbils=32
Mice=??
Rats=??
First, we have to find the numbers of Mice.
(Reducing Ratios divide them by a number like 2:4=1:2)
If you have 32 Gerbils and you reduced it to 4, what did you dived?
32/4=8
So, you multiply 7x8=56
There is 56 Mice.
Our table looks like this
Gerbils=32
Mice=56
Rats=??
Now we use the ratio 4:3 to find the numbers of Rats
If there are 56 mice, and it is reduced to 4, we have to do 56/4 to find out what we have to multiply 3 by to get the total numbers of rats (Inverse Operation) by. We get 14.
So now we do 3x14 in which we get 42.
Our chart now looks like this
Gerbils=32
Mice=56
Rats=42
I Hope this helped if you have any questions just tell me
50pt Which of the following are maximum and minimum points of the function y=sin(x+ π)?
Answer:
none of the above
Maximum (3π/2, 1); Minimum (π/2, -1)
Step-by-step explanation:
The sine function is shifted left 1/2 cycle by the addition of π to x in the argument. That basically inverts the function, so it is equivalent to ...
y = -sin(x)
This has a minimum of -1 at π/2, and a maximum of +1 at 3π/2. This does not match any of the offered answer choices.
__
You might want to discuss this question with your teacher.
Answer:
The correct answer is C!
Step-by-step explanation:
The dude that said there’s no answer doesn’t know what he’s talking about.
WILL MARK BRAINLIEST The width of a table is 2 feet less than the length. The area is 20 square feet. Find the dimensions. Show and
explain all work using mathematical concepts in this module.
Answer:
length ≈ 5.583 ft
width ≈ 3.583 ft
Step-by-step explanation:
If we let x represent the length of the table in feet, then the width is (x-2). The area is ...
A = LW
20 = x(x -2)
Writing this in standard form gives ...
x^2 -2x -20 = 0
The coefficients used in the quadratic formula are a=1, b=-2, c=-20. The solutions are ...
[tex]x=\dfrac{-b\pm\sqrt{b^2-4ac}}{2a}=\dfrac{-(-2)\pm\sqrt{(-2)^2-4(1)(-20)}}{2(1)}\\\\=\dfrac{2\pm\sqrt{4+80}}{2}=1\pm\sqrt{21}[/tex]
Of these values, the only one that makes sense is ...
length = 1+√21 ≈ 5.583 ft
width = length -2 ≈ 3.583 ft
Let width is x
length be x+2
Area=Length ×Breadthx(x+2)=20x²+2x=20x²+2x-20=0On solving
we get
x is around 3.58 or 3.6ft
Width=3.6ftLength=3.6+2=5.6fty = 7x
-14x + 2y = 0
The answer is no solution but please help with showing the work I’m stuck with it.
Answer:
-14x+2(7x)=0
-14×+14×=0
0=0
Find the least common denominator for these fractions. Enter your answer in
the space provided.
Answer:
10
Step-by-step explanation:
"Least" means smallest.
"Common" means same.
"Denominator " means the bottom number in a fraction.
Something/2 can be changed to something/10
AND something/5 can also be changed to
something/10
1/2 >>>> 5/10
3/5 >>>> 6/10
10 is the least common denominator.