If a cycliner has a radius of 4 in. and a height of 2in & you cut them in half along the length of the ...?

Question

-diameter, what would be the area of the bottom of the "cross section".

SEE DOESNT MAKE SENSE. The answer is like impossible to figure out!

the choices are 48,24, 16, 8.. i choose 24.. was i right or wrong?

Answer 1

cylinder is 4 inches wide and 2 inches tall

so r^2*3.14=
4 * 4 * 3.14 = 50.24 total
cut in half the area will be 25.12 square inches.
The height of the cylindar is not part of the question. It is just included to mislead you and check to see if you have learned the formula.

Answer 2

I think the bottom of the cross section would be the square made by cutting it down the middle??
Then it would be the length, times the height.
being, diameter times height.
Which is radius times 2 times height.
= 4 * 2 * 2
=16in.

Answer 3

You have a cylinder. It's bottom and top is a circle. You cut it along it's vertical length. You end up with a half circle.

The area of a circle is r*r*pi or r^2Pi
Half of that is (r^2Pi)/2

That is (4 * 4 * 3.14) /2

The problem is probaly trying to see if you can filter out an extreneous information which is the height.

Answer 4

sounds like find the area of an 8 inch diameter circle and cut it in half
If a circle has a radius of 4, its area is 3.14*4*4=50.24
cut in half the bottom cross section area would be 25.12
http://www.aaamath.com/B/geo612x2.htm

Answer 5

A cylinder...cut THEM... to me that's the part that doesn't make sense.

Then, once that's straightened out, you could build a rough pysical model out of an empty paper towel roll or something cylindrical to scale to get a better visual of the cross section. Maybe even measure it.

Answer 6

16 inches

Answer 7

question incomplete

Answer 8

6.474