Multiple choice:
979.68 centimeters squared
1507.2 centimeters squared
753.6 centimeters squared
1657.92 centimeters squared
2007-10-05 03:28:00 · 3 answers · asked by Anonymous in Science & Mathematics ➔ Mathematics
If you open up the cylinder it will look like a big square (and two circles if it is a closed cylinder)
The length of this square would be the circumferance of the circle = 2 pi r = 12pi
Height = 20 cm
Area = 20 x 12 x pi = 240 pi = 240 x 3.1415
= 754 cm2
The area of each circle is pi r2 = 3.1415 * 36 = 113 cm2
for both 226 cm2
Total = 980 cm2.
You need to know if its closed or open.
2007-10-05 03:35:45 · answer #1 · answered by blind_chameleon 5 · 0⤊ 0⤋
Hello
The lateral area of a cylinder is perimeter of base times its height.
Thus we have Circumference*Height = 2(pi)rh
LA = 2(pi)6(20) = 753.6 centimeters squared
Hope this helps
2007-10-05 10:32:53 · answer #2 · answered by Jeff U 4 · 0⤊ 0⤋
Lateral area of a cylinder = pi.d.height
=3.1416 x 12 x 20
= 753.98...
The closest answer is 753.6 cm^2 and hence is the right answer. The small difference is due to the slight difference in value of pi taken.
2007-10-05 10:35:10 · answer #3 · answered by Swamy 7 · 0⤊ 0⤋