Math Is Fun Forum

  Discussion about math, puzzles, games and fun.   Useful symbols: ÷ × ½ √ ∞ ≠ ≤ ≥ ≈ ⇒ ± ∈ Δ θ ∴ ∑ ∫ • π ƒ -¹ ² ³ °

You are not logged in.

#1 2015-07-31 08:55:29

owenflo
Member
Registered: 2014-07-21
Posts: 115

PLEASE SOMEONE HELP fast

I have a pizza. The radius is 10 inches long. The pizza was cut into 16 equal slices. When 1 slice was left, my sister and I both wanted it, so we agreed to cut it in half, but I like the crust more than she does, so we decided to cut it the "other way." In other words, the two pieces would not be symmetrical. The inside piece would contain all topping, and the outer piece would contain some topping and some crust.

5. What is the radius of a half-piece? (ie, where do I need to cut to make two equal halves out of a piece?)



NEXT QUESTION

If there is a goat tied to a rectangular barn on a 50 foot lead and the barn is 20 feet by 20 feet (floor), what is the maximum grazing area? If there are regions you can't find the area of, provide as good an estimate as you can. Assume the goat is tied to a corner outside the barn, cannot get in, and that the barn is not grazing area. (Remember, this will be based on parts of circles, no other shapes...the goat's rope will only get shorter when he tries to go around the barn...)


10. What is the total grazing area the goat can reach?

Offline

#2 2015-07-31 09:33:57

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Re: PLEASE SOMEONE HELP fast

Hi;

This question has been asked many times and what is amazing is they never even change the measurements or the shapes! They change the animal!!!!!!!! I have seen a goat, a puma, an elephant, a tyrannosaurus, a cow, a rhino and Prometheus tethered to that barn.

Here is some insight and the answer.

http://www.mathisfunforum.com/viewtopic.php?id=18412


In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

Offline

#3 2015-07-31 20:23:41

Bob
Administrator
Registered: 2010-06-20
Posts: 10,052

Re: PLEASE SOMEONE HELP fast

hi owenflo,

More from Compuhigh?  Don't they ever change their questions?

You will find a full analysis of both problems here:

http://www.mathisfunforum.com/viewtopic.php?id=18391

In the pizza question I have assumed that the cut is curved so that the smaller part is a sector of a smaller circle.  If you want a straight line cut I can probably do it but it will take a little longer.  As the exercise follows work on areas of circles I think it is safe to go with the curved cut.

Bob

bobbym wrote:

a goat, a puma, a elephant, a Tyrannosaurus, a cow, a rhino and Prometheus

Several on that list are meat eaters not grazers.  Not sure about Prometheus. smile


Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob smile

Offline

#4 2015-08-01 05:03:12

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Re: PLEASE SOMEONE HELP fast

That was stupid of me, Prometheus was on the field and the vulture was tethered. Thanks for spotting that.


In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

Offline

#5 2015-08-01 05:23:34

Bob
Administrator
Registered: 2010-06-20
Posts: 10,052

Re: PLEASE SOMEONE HELP fast

But that vulture ate his liver, so still no grazing.  smile

Bob


Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob smile

Offline

#6 2015-08-01 09:23:21

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Re: PLEASE SOMEONE HELP fast

Bearded Vulture in flight grazing

358311.jpg

http://www.juzaphoto.com/galleria.php?t=358311&l=en


In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

Offline

#7 2015-08-01 09:47:05

owenflo
Member
Registered: 2014-07-21
Posts: 115

Re: PLEASE SOMEONE HELP fast

I am still confused. Please help

Offline

#8 2015-08-01 14:17:19

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Re: PLEASE SOMEONE HELP fast

What confuses you?


In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

Offline

#9 2015-08-02 06:46:51

owenflo
Member
Registered: 2014-07-21
Posts: 115

Re: PLEASE SOMEONE HELP fast

This is what my teacher said...

#1-4  We measure length in inches.  But, we don't measure area in inches.  Area requires squared units.

#5  We don't have a triangle here . . . we have a circle sector.   I suggest that you use the formula for area of a circle, and solve for the radius of a half-pizza.

#10  Your work doesn't indicate what is being done with "75."  Also, what is your unit of measure?

Offline

#10 2015-08-02 06:51:17

owenflo
Member
Registered: 2014-07-21
Posts: 115

Re: PLEASE SOMEONE HELP fast

I have a pizza. The radius is 10 inches long. The pizza was cut into 16 equal slices. When 1 slice was left, my sister and I both wanted it, so we agreed to cut it in half, but I like the crust more than she does, so we decided to cut it the "other way." In other words, the two pieces would not be symmetrical. The inside piece would contain all topping, and the outer piece would contain some topping and some crust.

1. Find the area of the whole pizza.

2. What is the area of one piece of pizza?

3. What is the area of a half-piece?

4. What would the area of the whole pizza be if it were made of half pieces?

5. What is the radius of a half-piece? (ie, where do I need to cut to make two equal halves out of a piece?)


f there is a goat tied to a rectangular barn on a 50 foot lead and the barn is 20 feet by 20 feet (floor), what is the maximum grazing area? If there are regions you can't find the area of, provide as good an estimate as you can. Assume the goat is tied to a corner outside the barn, cannot get in, and that the barn is not grazing area. (Remember, this will be based on parts of circles, no other shapes...the goat's rope will only get shorter when he tries to go around the barn...)

10. What is the total grazing area the goat can reach?

Offline

#11 2015-08-02 07:03:17

Bob
Administrator
Registered: 2010-06-20
Posts: 10,052

Re: PLEASE SOMEONE HELP fast

You will find a full analysis of both problems here:

http://www.mathisfunforum.com/viewtopic.php?id=18391

B


Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob smile

Offline

Board footer

Powered by FluxBB