Question

PLEASE HELP!!! The figure shows the layout of a symmetrical pool in a water park. What is the area of this pool rounded to the tens place? Use the value = 3.14.


A) 1,180 square feet
B) 1,830 square feet
C) 2,120 square feet
D) 2,490 square feet
E) 2,630 square feet

Answer 1

Hi Sophia, this is a long proccess. I have to log out soon, however, if you're on right now and you're prompt to answer, we can go through this quickly.

Answer 2

im definitely ready! ive been stuck on this for a whole day now!!(: thank you so much!

Answer 3

No problem :) Well, first we identify shapes.

It seems like we have 4 triangles and two parts of circles. Imagine a cake - we're decorating it with different shapes and we need to know the area of each shape, so we take it apart to work out each shape's area individually.

Are you with me so far?

Answer 4

yes!

Answer 5

First, let's work out the area of the triangle.

Do you know the formula for the triangle?

Answer 6

A=1/2b*h right?

Answer 7

Yup, or bh/2. Calculate the triangle's area now.

Answer 8

250?

Answer 9

Yup! So now we have the triangles area - part of the pool. Now, one moment as I figure out the radian part - sorry.

Answer 10

ok, no worries!(:

Answer 11

I hope I got this correct, this is the formula for radian to degree->

(radians) (180/pi) = degrees.

180 is 180 degrees.

Source: http://www.learningaboutelectronics.com/Articles/How-to-convert-radians-to-degrees

Now input that and tell me your answer.

Answer 12

It's going to be in decimals - keep it on your calculator. DO NOT round off. We will be using the EXACT answer for the next sum to get the area.

Answer 13

so im confused, do I use the 250, and the 180?

Answer 14

250 = triangle area

180 = part of the formula to convert radian to degrees.

Answer 15

Different.

Answer 16

179.9087477?

Answer 17

Nope, show me what you wrote on your calculator.

Answer 18

3.14 * 180 / pi

Answer 19

Why did you input 3.14?

Answer 20

Do you know BODMAS?

Answer 21

idk/: , and yes!

Answer 22

(radians) (180/pi) = degrees.

^Formula

Find radian and substitute. Keep in mind and place brackets on your calculator too.

Answer 23

I you don't put brackets...this is what the equation will equal:

radians*180/pi <<<Completely WRONG as it's calculated in wrong order.

Answer 24

126.623672724?

Answer 25

Yup! One moment again as I work out the sector area formula....^^;;; Sorry!

Answer 26

Sorry I took so long, I got messed up with the formula for segments. The formula for the area of a sector (which is what you have) is:

pi*r^2*ANS/360

ANS = Angle you got. DO NOT INPUT THE ROUNDED VERSION, INPUT ANS WHICH GIVES THE EXACT ANSWER.

Answer 27

ok hold on let me try!

Answer 28

Whilst you try, I can explain this formula to you as I know it (the radian - I have no idea >_>).

You know percentages? pi*r^2 = full circle.

So multiplying by angle/360 you get part of the circle. 360 is full revolution = full angle of circle.

Answer 29

5.3969305?

Answer 30

Nope. Show me your calculations.

Answer 31

π × 2.21^2 × 126.623672724 ÷ 360

Answer 32

My bad, r = radius, not radian. I assumed you knew that :/
Radius = 30 feet. Look in your diagram. That's radius - completely different to radian.

Now, please re-do the radian to degrees equation (because you need the exact answer) and re-do the sector area formula.

Answer 33

Oh and :/ is for me, not directed to you :)

Answer 34

I understand, that's my fault! im sorry. hold on one second. let me try agaib!

Answer 35

994.500000001?

Answer 36

Good! Something's wrong with my calculator, I only got up to 994.5 but that's good so far. Now, multiply that by 2 as you have 2 sectors.

So its:

(Ans * 2) + (250*2) <<<Adding up the area of two sectors and the area of two triangles.

Remember brackets! Then round. Your question is finished!

Answer 37

2489.00000001

so the answer is D! thank you so so much for all the help and patience!!

Answer 38

No problem, I've learnt some new things too, thanks to you. Great job, I appreciate your enthusiasm through the process! :)