Simple Maths

rectum

huh

i mean : rectangle

2. BODMAS is fighting for position with xylem as my favourite word.

  On 4/9/2011 at 4:18 PM, Dirty Protest said:

2. BODMAS is fighting for position with xylem as my favourite word.

phloems are better

Real mathematicians avoid these situations.

yes, mathematicians avoid arithmetic at all costs

lol.

Here's another one.

A guy buys a chicken for 8 dollars. He then sells that chicken for 9 dollars. Then he buys the same chicken back for 10 dollars, and sells it off again for 11 dollars.

How much money did he make in this deal?

This is the third forum I've seen this problem. It's badly written out. Add the brackets, then proceed from left to right and you get 288.

  On 4/9/2011 at 5:53 PM, disparaissant said:

Here's another one.

A guy buys a chicken for 8 dollars. He then sells that chicken for 9 dollars. Then he buys the same chicken back for 10 dollars, and sells it off again for 11 dollars.

How much money did he make in this deal?

$2

  On 4/9/2011 at 6:02 PM, azatoth said:

This is the third forum I've seen this problem. It's badly written out. Add the brackets, then proceed from left to right and you get 288.

Its not. Read it as 48 ÷ xy

  On 4/9/2011 at 6:09 PM, luke viia said:

I didnt make the rules m8 =)

i dunno about the notation sucking, looks perfectly legit to me, and as it is can only equal 2.

parentheses multiplication always comes first, that's the whole point.

  On 4/9/2011 at 6:09 PM, luke viia said:

and no, it's not that.

multiplication and division occur at the same stage in the order of operations, and must be done left to right.

did you lift this form teamliquid?

imo if you place a number right next to some quantity instead of using a multiplication symbol, it will most likely mean that it is all one quantity, so 48÷2(9+3) and 48÷2*(9+3) are simply not the same thing for anyone that's used to math, the first is 2 and the second is 288. It's not a rule like pemdas, but pemdas isn't a really a rule people use when working with math (I doubt it's even taught outside the anglo world), the actual rule about this is: WRITE YOUR MATH SO THE MEANING IS CLEAR.

nope. with or without the *, both are equivalent and give the same result. at least, that is what is being taught at this side of the lake.

"it will most likely mean"

here lies the problem. designing purely arithmetical expressions to "most likely" mean something is the sign of a mathematically challenged dingus. as you say, write that shit so the meaning is clear. the parentheses do indeed mean the exact same thing as * would in this expression. even if we used variables, the parentheses wouldn't change the fact that you have to deal w/ the 48 before you go all willy nilly fucking around with the 12.

  On 4/9/2011 at 5:53 PM, disparaissant said:

Here's another one.

A guy buys a chicken for 8 dollars. He then sells that chicken for 9 dollars. Then he buys the same chicken back for 10 dollars, and sells it off again for 11 dollars.

How much money did he make in this deal?

How much money did he earn or how much money did he make?

Coincidentally - this is exactly what went on in the Savings and Loan scandal in the 80s.

A buys useless plot of land for 5k

A sells useless plot of land to B for 10k

B sells useless plot of land back to A for 20k

A sells back to B for 50k.

B sells to C for 50k and voila A and B are 45k richer.

  On 4/9/2011 at 5:53 PM, disparaissant said:

Here's another one.

A guy buys a chicken for 8 dollars. He then sells that chicken for 9 dollars. Then he buys the same chicken back for 10 dollars, and sells it off again for 11 dollars.

How much money did he make in this deal?

Let t_1 the first time of purchase of the chicken, t_2 the first time of selling of it, t_3 the second time of purchase of it, and t_4 the last sale time, all expressed in years. if r is the (continuosly compunded) risk-free interest rate and we assume that it's constant during the whole enterprise, the value of the operation is.

2 - 8e^(r(t_2 - t_1)) - 10e^(r(t_4 -t_2))

:p

  On 4/9/2011 at 6:33 PM, chenGOD said:

Coincidentally - this is exactly what went on in the Savings and Loan scandal in the 80s.

A buys useless plot of land for 5k

A sells useless plot of land to B for 10k

B sells useless plot of land back to A for 20k

A sells back to B for 50k.

B sells to C for 50k and voila A and B are 45k richer.

  On 4/9/2011 at 6:33 PM, chenGOD said:

  On 4/9/2011 at 5:53 PM, disparaissant said:

Here's another one.

A guy buys a chicken for 8 dollars. He then sells that chicken for 9 dollars. Then he buys the same chicken back for 10 dollars, and sells it off again for 11 dollars.

How much money did he make in this deal?

 

How much money did he earn or how much money did he make?

 

Coincidentally - this is exactly what went on in the Savings and Loan scandal in the 80s.

A buys useless plot of land for 5k

A sells useless plot of land to B for 10k

B sells useless plot of land back to A for 20k

A sells back to B for 50k.

B sells to C for 50k and voila A and B are 45k richer.

why did C buy useless plot of land for 50k? the whole back and fort is pretty unnecessary to make the profit, or was that a way to fake demand and inflate prices?

Three sailors decided to share a motel room for $30 a night or $10 each. After they've checked in the manager feels guilty for charging so much, so he gives the bellhop $5 to take to the sailors. The porter is mad at the sailors for not tipping him, so he keeps $2 and gives each man $1.

Each sailor now has paid $10 - $1 = $9. $9 x 3 = $27. Add the $2 the bellhop kept and we have $29. Where is the other dollar?

No Cheating now.

  On 4/9/2011 at 6:43 PM, GORDO said:

  On 4/9/2011 at 6:33 PM, chenGOD said:

  On 4/9/2011 at 5:53 PM, disparaissant said:

Here's another one.

A guy buys a chicken for 8 dollars. He then sells that chicken for 9 dollars. Then he buys the same chicken back for 10 dollars, and sells it off again for 11 dollars.

How much money did he make in this deal?

 

How much money did he earn or how much money did he make?

 

Coincidentally - this is exactly what went on in the Savings and Loan scandal in the 80s.

A buys useless plot of land for 5k

A sells useless plot of land to B for 10k

B sells useless plot of land back to A for 20k

A sells back to B for 50k.

B sells to C for 50k and voila A and B are 45k richer.

 

why did C buy useless plot of land for 50k? the whole back and fort is pretty unnecessary to make the profit, or was that a way to fake demand and inflate prices?

Answered your own question :)

  On 4/9/2011 at 7:58 PM, ZiggomaticV17 said:

Three sailors decided to share a motel room for $30 a night or $10 each. After they've checked in the manager feels guilty for charging so much, so he gives the bellhop $5 to take to the sailors. The porter is mad at the sailors for not tipping him, so he keeps $2 and gives each man $1.

 

Each sailor now has paid $10 - $1 = $9. $9 x 3 = $27. Add the $2 the bellhop kept and we have $29. Where is the other dollar?

 

No Cheating now.

that one always gets me even tho i already know the error, i have to always go around it for ages.