TM 9-243
READING THE SCALE OF A RULE OR TAPE - Continued
To determine the number of 64ths in 3/4, remember
every sixteen divisions or 16/64 are equal to 1/4 inch. If
1/4 is equal to 16/64, then 3/4 is equal to 48/64 as
shown:
If 1/4 = 16/64, then 3/4 = 48/64
(16x3=48)
1
Locate the number 48 between the 2 and 3 inch
marks on the scale.
2.
Write the new fraction 2-48/64.
READING A METRIC RULE
The metric system is based upon multiples of ten. For
example, there are 10 millimeters in a centimeter and
100 centimeters in a meter.
The example provided will deal only with millimeters
(mm).
The meter will become the starting point and from-this,
two additional scales can be developed for measuring.
A meter divided by 100 equals a centimeter (cm), 1/100
or 0.01 meter.
Next divide a centimeter (cm) by 10. This will equal a
millimeter (mm), 1/1000 or 0.001 meter.
Now let’s look at a section of the rule between 2 cm and
3 cm.
There are 10 equal divisions which are equal to 1/10 cm
or 1 mm.
To measure 26 mm, first locate the longest line desig-
nated 2 cm or 20 mm.
Next count 6 additional lines to find 26 mm.
A table for converting from US Common to metric or
from metric to US Common may be found inside the
back cover of this manual.
3-3/(3-4 blank)
