9190
4. Determining Square Root
Problem:What is the square root of 225?
Solution:Rotate the scales so that the value on the inside scale corresponding to 22.5
on the outside scale is equal to the value on the outside scale corresponding
to 10 on the inside scale, and read off the answer of 15 at that location.
3. Reading Ratios
Problem: 30/20 = 60/x
Solution:Align 30 on the outside scale with 20 on the inside scale. At this time, the
answer of 40 can be read from the inside scale corresponding to 60 on the
outside scale. In addition, the ratio of the value on the outside scale to the
value on the inside scale is 30:20 at all positions on the scales.