Why is it 3.14XXX...?
2007-02-20 00:17:29 · 12 answers · asked by Eloy 213 2 in Science & Mathematics ➔ Mathematics
Becuase "Pie" is a round, baked dessert, and we don't know how many you ordered.
Or maybe you meant to say "Pi"?
Pi does indeed have an exact value. We can caclulate it to however many decimal places as we want. But the decimals never end, and there's no pattern to them, thus we can never write out a value that gives its exact value without any rounding off, because that would take an infinite number of decimals.
We KNOW FOR A FACT that Pi does this because Pi is an irrational number. Rational numbers always have a decimal that terminates or at some point repeats. Not so with irrational numbers. The proof is a little long to put here, but it was proven a couple of centuries ago that Pi is an irrational number.
And as other people have pointed out, Pi is NOT equal to 22/7. That is ONLY an approximation. It's only accurate to the nearest hundreth. And 22/7 is NOT an irrational number, because if you were to use long division to calculate 22 divided by 7, you'll notice that a certain pattern of decimals eventually keep repeating forever.
Pi is hardly the only irrational number out there. There's also the square root of 2, and the expoential number "e" for example.
2007-02-20 00:54:37 · answer #1 · answered by Anonymous · 0⤊ 0⤋
Exact numbers (1, 2, 3, ...) are used for counting things. Pi is not a "thing" that can be counted. Pi is the ratio of a perfect circle's circumference divided by its diameter. The ratio of a square's edge (4") divided by its width (1") = 4 which is exact. The ratio for the circle is never exact regardless of how detailed the math.
2007-02-20 02:23:33 · answer #2 · answered by Kes 7 · 0⤊ 0⤋
"Because it is a transcendental figure without resolution."
That means the digits after the decimal point just go on and on for ever without repeating. So you could never find them all out, or write them all down, there would always be more. Numbers like this are also called "irrational".
Of course, this is just a re-statement of the question.
There may be some deep mathematical reason why Pi is irrational and there's bound to be a proof that it is, but we are getting into the realms of advanced pure maths now.
NOTE : PI IS ABSOLUTELY NOT 22/7
That is WRONG WRONG WRONG.
22/7 is a fairly good approximation to Pi, but it is not equal to it.
2007-02-20 00:32:31 · answer #3 · answered by lawomicron 4 · 1⤊ 0⤋
It is the ratio of a circles radius to its circumference and area.
A circle is a shape which theoretically has an infinite amount of sides. Therefore pi is the exact ratio of radius to circumference. If something has an infinite amount of sides, the result is a arithmetic series with an infinite amount of terms.
2007-02-20 00:54:30 · answer #4 · answered by Doctor Q 6 · 0⤊ 0⤋
pie is the sum of an infinite series
pie= 4 - (4/3) + (4/3) ^ 2 - (4/3) ^ 3 + (4/3) ^ 4 - ......+.......
so its value will never be constant so we approximate it.
anyway u can try to add and subtract value until you got tired but after 15 try the answer will not change a lot.
good luck
2007-02-20 00:42:44 · answer #5 · answered by babilla1983 1 · 0⤊ 1⤋
I wished someone had told me about numbers when I was younger, but think of the realm of real numbers as they exist. Numbers can be represented in three columns: Percents, Decimal, Ratio. Each row going across the three columns represents the same value, the same number.
pi is a ratio, which can also be described as a Decimal (3.14....) or the percentage of a circle (radians) or to mark it as a ratio, in whole numbers, pi is 22/7 but it doesn't divide evenly. So, carry the remainder, divide, carry the remainder, divide and so on, there is no end.
2007-02-20 00:29:23 · answer #6 · answered by Anonymous · 0⤊ 3⤋
There is no exact value posible of Pi, because it is an irrational number
2016-05-23 22:20:32 · answer #7 · answered by Anonymous · 0⤊ 0⤋
Well, I am not too sure why you cant understand this... but. 22/7 goes on forever. so ya, there could be an exact number, we just havnt found it yet
2007-02-20 00:40:06 · answer #8 · answered by alexprice1212 2 · 0⤊ 2⤋
As far as we can tell, it is a nonrepeating decimal.
FYI...22/7 is only an approximation.
2007-02-20 00:30:45 · answer #9 · answered by gebobs 6 · 0⤊ 1⤋
because 3.14XXX is the most basic numeral for PIE. if PIE were to be the exact number it would be 3.1495XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
forever and ever. so we use the simple 3.14 for PIE to make our lives easier.
2007-02-20 00:37:42 · answer #10 · answered by Anonymous · 0⤊ 1⤋