Find the length of the radius of a sphere with a volume of 14.14 mm3.

Question

anonymous · Answer

answers: 
   3.6 mm 
   1.8 mm 
   3.0 mm 
   1.5 mm

blurbendy · Answer

Volume of a sphere = 4/3(pi)r^3

You need to solve for r

anonymous · Answer

I don't know what r is tho and im so confuseddd.

blurbendy · Answer

r stands for for radius, which is what you're trying to find.  to start, just substitute known values into the formula.

14.14 = 4/3(pi)r^3

anonymous · Answer

oh wait I do know what r is  but I don't know what to do .

blurbendy · Answer

you'd start by dividing both sides by 4/3pi

anonymous · Answer

that gives me 3.7

blurbendy · Answer

i got something around 3.38

blurbendy · Answer

so you have 3.38 = r^3

now take the cubed root of both sides and you'll then have what the radius is

anonymous · Answer

1.8?

blurbendy · Answer

you can rewrite the cubed root of 3.38 as 3.38^(1/3)

blurbendy · Answer

which is... ?

anonymous · Answer

it gave me 1.1 ?

blurbendy · Answer

anonymous · Answer

ohhhh wow this is so confusing so itd be 1.5?

blurbendy · Answer

yes.  just be careful when you're entering things in your calculator.  Parentheses are important

anonymous · Answer

ohk thanks :)

blurbendy · Answer

yw