The usual procedure to find a*b is to set 1 on C opposite a on D, and read the answer on D opposite b on C. If that is off the scale, you must use the alternative procedure of setting 10 on C opposite a on D, and read the answer on D opposite b on C.
To find 7.92*pi, set 10 on C opposite 7.92 on D; read answer on D opposite pi on C (which is indeed 2.49E1, according to my 6" rule).
Alternatively, set 10 on C opposite pi on D; read answer on D opposite 7.92 on C. The two should be the same.
(You get more accuracy by using the C and D scales which, unlike A and B, do not compress 1.0-10.0 into half the length of the rule.) |
