( use 3.14 for PI)
2007-07-24 01:58:13 · 8 answers · asked by @_@ 4 in Science & Mathematics ➔ Mathematics
13.188 is correct!
- asking a million math questions to see kno knows them is fun.
2007-07-24 02:03:37 · update #1
C= PI x Diameter
C= PI x (2 x radius)
C = 3.14 x 2 x 2.1
C = 13.19 cm.
♥ study your basic math! lol ^_^
edit: Hakuri, when you specified PI to be equal to 3.14, it means it has only 2 decimal places, meaning the answer should be expressed with only 2 decimals too.. so, that should be 13.19, if what you needed was 13.188, then you should have specified PI as 3.1416 so as the answerer could express the final answer to approximate values...
2007-07-24 02:03:07 · answer #1 · answered by Anonymous · 0⤊ 0⤋
Cir = pi * 2 radius
= 3.14 *2 * 2.1 = 13.188 or round to 13.19 cm
2007-07-24 02:06:27 · answer #2 · answered by Anonymous · 1⤊ 0⤋
the circumference : C = 2*pi*r
substitute your 2.1 for your radius. Have fun!!
2007-07-24 02:05:03 · answer #3 · answered by Shelly 1 · 0⤊ 0⤋
C = 2 Ï r
C = 4.2 Ï
C = 13.19 cm (to 2 dec. places)
2007-07-26 07:15:25 · answer #4 · answered by Como 7 · 0⤊ 0⤋
use 2*pi*r and use a calculator
2007-07-24 02:00:50 · answer #5 · answered by Anonymous · 0⤊ 0⤋
c = pi * d (diameter) = pi * 2r = pi * 4.2 = 13.188 cm (approx)
2007-07-24 02:01:50 · answer #6 · answered by John V 6 · 0⤊ 0⤋
27.6948cm^2
2007-07-24 02:02:50 · answer #7 · answered by koooooooooooool 2 · 0⤊ 2⤋
it is approximately 13.188
2007-07-24 02:29:55 · answer #8 · answered by JJ JAMZ 3 · 0⤊ 0⤋