Chapter 47, Problem 36A

Compute the following problems. Express the answers to the nearest whole number. Use $N=\frac{12C}{3.1416D}$ or $\frac{12C}{\pi D}$ for customary units and $N=\frac{1000C}{3.1416D}$ or $\frac{1000C}{\pi D}$ for metric units.
An annealed cast iron housing is drilled with a cutting speed of 20 meters per minute using a 22-millimeter diameter carbon steel drill. Find the revolutions per minute.