I cannot figure this out. It seems so simple, and I should know it.

Question

The density of tungsten is 19.3g/cm^3
Express this value in lb/ft^3.

I did 19.3g/cm^3 x 2.54cm/inch x 12 inches/1 foot = 588.264.

Now 19.3g x 1 ounce/28g x 16 ounces/lb.
= 11.03.

After reading my answer key, the answer says it is 1.21 x 10^3 lb/ft^3.

I cannot for the life of me figure out what I am doing wrong. Please help.

Answer 1

19.3 g/1 cm^3 * 1 lb/453.59 g
=0.043 lb/cm^3
The grams cancel out.
0.043 lb/cm^3 * 28317.02 cm^3/ft^3=1217.63 lb/ft^3

1217.63 lb/ft^3 = 1.21 lb/ft^3

Answer 2

Thankyou very much