Example 42.—2/24's worsted yarn has been used for an order and runs out before completion of the weight required; sufficient weight of 16's is in stock, find the nearest counts which must be used along with this to give a fabric of the same weight as the original; 2/24's = 12's.
Using the rule of differences—
| 16 × 12 | |
| = 48's. | |
| 16 - 12 |
The ratio of weights can be found thus, 48's and 16's—
| 48 hanks of 48's = | 1 lb. |
| 48 hanks of 16's = | 3 lb. |
| 4 lb. |
That is, out of a total of 4 lb. one-quarter is of the finer counts 48, whilst the remaining three-quarters is of the second counts 16's. By making this calculation it will be seen whether there is a sufficient weight of each yarn to complete the order.
Example 43.—As a substitute for solid 2/22's yarn in a garment it is proposed to use one thread of 18's and a second yarn of suitable size to give the same weight. Find this yarn and state the ratio in which the two will occur in the garment.
By the rule of differences—
| 18 × 11 | 18 × 11 | ||
| = | = 282⁄7 counts. | ||
| 18 - 11 | 7 |
For the weight of each, this can be done quite simply by adding the two counts and taking the relative proportions inversely—