ACT Math: Plane Geometry Drill 4, Problem 1. What is the radius of the sphere?
|ACT Math||Plane Geometry|
|ACT Mathematics||Plane Geometry|
|Foreign Language||Arabic Subtitled|
|Plane Geometry||Applications of geometry to three dimensions|
Simple 3D geometry
|Product Type||ACT Math|
is the radius from the center of the Earth to the crispy crust.
That's R. That formula: four-thirds times quantity pi R cubed.
We just need to solve for R. So for starters...
multiply both sides by three-fourths and we have pi R cubed
equals three-fourths times 288 pi. Rewrite the equation
as pi R cubed equals 216 pi
and we can get rid of the pi on both sides by dividing it out and we're left
with R equals the cube root of 216.
So the answer is 6 and yeah, 216 is a way out their number
so you can just started by multiplying out three times three to get nine times
three with just 27. Too low. Then try four
and five and you have found your way to six pretty quick.
Anyway, the answer is R equals 6 or answer C.