Question

If a sphere has a radius 15 m, what is the volume of the hemisphere? I plugged in the formula and if im doing this correctly i got 14130, divided by 2 to find the hemisphere and got 7065 but thats not an option so i want to know where i went wrong?

Answer 1

what answer choices do you have

Answer 2

4500 π m3
9000 π m3
2250 π m3
1125 π m3

Answer 3

*m^3

Answer 4

ok so you don't use 3.14 for pi, you just leave it alone

Answer 5

wait how do i leave out pi?

Answer 6

think of pi as a variable, don't replace it with 3.14

Answer 7

does that make sense?

Answer 8

.. now im really lost..

Answer 9

what is the formula you used

Answer 10

4/3 π 15^3

Answer 11

it has a pi in it, so compute it without the pi in it

then at the very end, just tack on 'pi'

Answer 12

ok so 4/3x15^3?

Answer 13

that's the volume of a sphere

you would cut that in half to get 4/6 pi*15^3 or 2/3 pi * 15^3

which is now the volume of a hemisphere

Answer 14

yes do all of your calculations without pi

Answer 15

or n

Answer 16

then at the very end, tack on a pi symbol

Answer 17

ok give me a second

Answer 18

alright

Answer 19

i dont have a scientific calculator so im using the laptop calculator and i cant figure out how to use a variable -_-

Answer 20

ignore the variable

pretend the pi isn't there at all until the very end

Answer 21

will that work?

Answer 22

oh wait 4500?

Answer 23

yes it will

Answer 24

now cut that in half

Answer 25

i wish i could give you more medals

Answer 26

because you're dealing with a hemisphere

Answer 27

so it's really 2250

then you tack on pi to get the answer of 2250pi

Answer 28

ok so 2250. thank you!

Answer 29

yes, yw