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
alukav5142 [94]
4 years ago
13

A park is in the shape of a rectangle. The park authorities are planning to build a 2-meter-wide jogging path in the park (shown

as the shaded region in the image). What is the area of the jogging path?

Mathematics
1 answer:
Burka [1]4 years ago
5 0
First, we need to find the area of the two rectangles in this picture. We know that area = l*w.

So for the larger rectangle, we know the l = 100 m, and the w = 60 m. Let us find the area:

A=100*60=6000 m^{2}

So the larger rectangle area is 6000 m.

The smaller rectangle has dimensions that are 2 m less on every side. So we can recalculate these dimensions as l = 96 m and w = 56 m.

Let's find the area of the smaller rectangle:

A=96*56=5,376 m^{2}

So we know that the area of the smaller rectangle is 5,376 m.

The area of the jogging path is going to be the difference between these two rectangles. Let us solve:

6,000-5,376=624 m^{2}

So now we know that the area of the jogging path is 624 m^{2}.
You might be interested in
What are all the subsets of {5,9,13}
Naddika [18.5K]
All The Subsets

For theset {a,b,c}:

<span>The empty set {} is a subset of {a,b,c}And these are subsets: {a}, {b} and {c}And these are also subsets: {a,b}, {a,c} and {b,c}And {a,b,c} is a subset of {a,b,c}</span>

And when we list all the subsets of S={a,b,c} we get the Power Set of {a,b,c}:

P(S) = { {}, {a}, {b}, {c}, {a, b}, {a, c}, {b, c}, {a, b, c} }

Think of it as all the different ways we can select the items (the order of the items doesn't matter), including selecting none, or all.

Example: The shop has banana, chocolate and lemon ice cream.

 

What do you order?

<span>Nothing at all: {}Or maybe just banana: {banana}. Or just {chocolate} or just {lemon}Or two together: {banana,chocolate} or {banana,lemon} or {chocolate,lemon}Or all three! {banana, chocolate,lemon}</span>

Question: if the shop also has strawberry flavor what are your options? Solution later.

How Many Subsets

Easy! If the original set has n members, then the Power Set will have <span>2n</span> members

Example: in the {a,b,c} example above, there are three members (a,b and c).

So, the Power Set should have 23 = 8, which it does!

Notation

The number of members of a set is often written as |S|, so when S has n members we can write:

|P(S)| = 2n

Example: for the set S={1,2,3,4,5} how many members will the power set have?

Well, S has 5 members, so:

|P(S)| = 2n = 25 = 32

You will see in a minute why the number of members is a power of 2

It's Binary!

And here is the most amazing thing. To create the Power Set, write down the sequence of binary numbers (using n digits), and then let "1" mean "put the matching member into this subset".

So "101" is replaced by 1 a, 0 b and 1 c to get us {a,c}

Like this:

<span><span> abcSubset</span><span>0000{ }</span><span>1001{c}</span><span>2010{b}</span><span>3011{b,c}</span><span>4100{a}</span><span>5101{a,c}</span><span>6110{a,b}</span><span>7111{a,b,c}</span></span>

Well, they are not in a pretty order, but they are all there.

Another Example<span>Let's eat! We have four flavors of ice cream: banana, chocolate, lemon, and strawberry. How many different ways can we have them?Let's use letters for the flavors: {b, c, l, s}. Example selections include:<span>{} (nothing, you are on a diet){b, c, l, s} (every flavor){b, c} (banana and chocolate are good together)etc</span></span>Let's make the table using "binary":<span><span> bclsSubset</span><span>00000{}</span><span>10001{s}</span><span>20010{l}</span><span>30011{l,s}</span><span>...... etc ..... etc ...</span><span>121100{b,c}</span><span>131101{b,c,s}</span><span>141110{b,c,l}</span><span>151111{b,c,l,s}</span></span>

And the result is (more neatly arranged):

P = { {}, {b}, {c}, {l}, {s}, {b,c}, {b,l}, {b,s}, {c,l}, {c,s}, {l,s}, {b,c,l}, {b,c,s}, 
{b,l,s}, {c,l,s}, {b,c,l,s} }


<span><span>SymmetryIn the table above, did you notice that the first subset is empty and the last has every member?But did you also notice that the second subset has "s", and the second last subset has everything except "s"?</span><span>  </span><span>In fact when we mirror that table about the middle we see there is a kind of symmetry.This is because the binary numbers (that we used to help us get all those combinations) have a beautiful and elegant pattern.</span></span>A Prime Example

The Power Set can be useful in unexpected areas.

I wanted to find all factors (not just the prime factors, but all factors) of a number.

I could test all possible numbers: I could check 2, 3, 4, 5, 6, 7, etc...

That took a long time for large numbers.

But could I try to combine the prime factors?

Let me see, the prime factors of 510 are 2×3×5×17 (using prime factor tool).

So, all the factors of 510 are:

<span>2, 3, 5 and 17,2×3, 2×5 and 2×17 as well, and2×3×5 and 2×3×17 and ..... aha! Just like ice cream I needed a Power Set!</span>

And this is what I got:

<span><span> 2,3,5,17SubsetFactors of 510</span><span>00000{ }1</span><span>10001{17}17</span><span>20010{5}5</span><span>30011{5,17}5 × 17 = 85</span><span>40100{3}3</span><span>50101{3,17}3 × 17 = 51</span><span> ... etc ...... etc ...... etc ...</span><span>151111{2,3,5,17}2 × 3 × 5 × 17 = 510</span></span>


And the result? The factors of 510 are 1, 2, 3, 5, 6, 10, 15, 17, 30, 34, 51, 85, 102, 170, 255 and 510 (and −1, −2, −3, etc as well). See the All Factors Tool.

Automated

I couldn't resist making Power Sets available to you in an automated way.

So, when you need a power set, try Power Set Maker.

6 0
3 years ago
Read 2 more answers
Can someone help me with 3,4 and 5? For 3 and 4 it's asking "what is the volume of each solid? Round to the nearest tenth if nec
Marianna [84]

Answer:

the answer 3,b

4,f

5,c

7 0
3 years ago
ANSWER ASAP PLS 20 POINTS! Which graph represents the piecewise defined function? y= {3 if x&lt;-2 0 if x=1 -1 if x&gt;1
Otrada [13]

Answer:

It is the third option. (the one which has a black point at X=1, Y=1)

Step-by-step explanation:

For simplicity what you should do is, you should satisfy the second condition that is, y=0 if x=1.

Here only the third option is satisfying this condition.

Whenever there is is a white circle or a white point it means that the point does not satisfy the condition and the the function is not defined at that point. And the black point means that the circle is defined at that point and satisfies the condition.

Henceforth, the correct answer is the third option.

4 0
4 years ago
Can you help me?
Semenov [28]

Answer:

0=0

Step-by-step explanation:

8 0
3 years ago
URGENT: If θ is a second-quadrant angle and cosθ = -2/3, then tanθ = _____.
dangina [55]

In the second quadrant, both cos and tan are negative while only sin is positive.

To find tan, we will use the following property below:

\large \boxed{ {tan}^{2}  \theta  =  {sec}^{2}   \theta - 1}

Sec is the reciprocal of cos. If cos is a/b then sec is b/a. Since cos is 2/3 then sec is 3/2

\large{ {tan}^{2}  \theta =  {( -  \frac{3}{2}) }^{2}  - 1} \\   \large{ {tan}^{2}  \theta =   \frac{9}{4}  - 1} \\   \large{ {tan}^{2}  \theta = \frac{9}{4}   -  \frac{4}{4} \longrightarrow  \frac{5}{4}  } \\  \large{tan \theta =  \frac{ \sqrt{5} }{ \sqrt{4} } } \\  \large \boxed{tan \theta =  \frac{ \sqrt{5} }{2} }

Since tan is negative in the second quadrant. Hence,

\large{ \cancel{ tan \theta  =  \frac{ \sqrt{5} }{2} } \longrightarrow \boxed{tan \theta =  -  \frac{ \sqrt{5} }{2} }}

Answer

  • tan = -√5/2
3 0
3 years ago
Other questions:
  • can some on help me that way smarter wants the expression in words for 9×(8+4) and plz show me how to write it
    5·1 answer
  • Find the sum of the first 35 terms in this geometric series <br><br> 8 - 12 + 18
    5·1 answer
  • Help plz
    6·2 answers
  • the slope of the line below is 2. use the labeled point to find a point-slope equation of the line. (1, 9)
    15·1 answer
  • What is the expanded form 4,365,421,006
    7·1 answer
  • Question is link so do that.
    7·1 answer
  • Which expression is equivalent to 1/3(4x+9)+5x?
    12·2 answers
  • Rewrite in simplest terms -5(3u + 1) + 10
    5·1 answer
  • ​4 quarter hours = ​<br> hours
    5·2 answers
  • 2. in the figure, x is an exterior angle to the triangle below. (
    12·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!