Question

A cylinder and a rectangular prism have the same volume and same height. The base of the prism is a square with side length 9 cm.

What is the approximate radius of the cylinder?

A.
4.5 cm

B.
5.1 cm

C.
12.9 cm

D.
25.8 cm

AND PLEASE EXPLAIN BECAUSE IM SO CONFUSED

Answer 1

Volume of prism is 1/3 * area of base* height
in this case base is square
so we will put the area of square
and volume of cylinder is pi * r^2 * height
equate both the volumes u will surely get your answer

Answer 2

and so 9 is the area ? @niksva

Answer 3

area of square = (side)^2
here side is 9
so can u determine the area?

Answer 4

whats the ^ mean

Answer 5

9 multiplied by two which is 81? the area

Answer 6

9^2 means 9 raised to power 2 which is 81

Answer 7

oh yeah 9 squared

Answer 8

can you draw something showing how to find the approximate radius

Answer 9

now equate the volume in this this manner
\[\pi*r^2h = \frac{ 1 }{ 3 }* area of \square * h\]

Answer 10

now you can determine radius

Answer 11

whats the f mean im in the 6th grade @niksva

Answer 12

your equation says that i have to multiply the radius and height when i dont even know the radius and height @niksva

Answer 13

@jim_thompson5910 can u help

Answer 14

can anyone help

Answer 15

height of prism and cylinder are equal
so height will be cancelled out
and u need to determine the radius

Answer 16

is it B. 5.1

Answer 17

oohoho its D

Answer 18

i was just gonna say that

Answer 19

because...

Answer 20

9 * 9 is 81 then you divide 81 by 3.14

Answer 21

\[22/7 * r^2 = 1/3 *81\]

Answer 22

yay

Answer 23

sorry
we are not going to multiply by 1/3 in prism
r^2 = 81/3.14

Answer 24

divide it now and then take the square root
u will get the radius

Answer 25

oh ok

Answer 26

so answer will be B

Answer 27

thx @niksva

Answer 28

and formulae for volume of prism is area of base * height
pls do make that correction

Answer 29

k but its still B right @niksva

Answer 30

yup

Answer 31

one more question its small

Answer 32

the exact answer is closest to the answer than the approximate right

Answer 33

im pretty sure it is

Answer 34

exact answer is 5.07 cm
approximate answer is 5.10 cm

Answer 35

forget it