| 20 × 7,000 | 500 | ||
| = | or 166⅔. | ||
| 840 | 3 |
Example 4.—Find the counts of a merino yarn of which 20 yd. weigh 14 grains.
Taking the value 500⁄3 divide it by 14, thus—
| 500 | |
| = 11·9 counts. | |
| 3 × 14 |
Similarly, if working with dram weights and a standard length of 20 yd. we should devise a value for the figures constantly recurring and this would greatly simplify the calculation of the counts.
Example 5.—Find the counts in Galashiels or Scotch woollen system of a yarn, 20 yd. of which weigh 2 drams.
The first step is to find the yards in 1 lb. = 16 × 16 = 256 drams, and then divide by the hank length of 200 yd.—
| 20 × 256 | |
| = 12·8 cut Scotch woollen. | |
| 2 × 200 |
In all calculations of this character the numbers 20 × 256
200 will occur and these reduced give a value of 25·6 which is taken as the constant and for all similar calculations the weight in drams is simply divided into this value to obtain the result.
Example 6.—Find the counts in Scotch woollen of a yarn, 20 yd. of which weigh 1·25 grains.