| 80 ÷ 80 | = | 1 | lb. @ | 15/- | = 15/- |
| 80 ÷ 14 | = | 5·7 | lb. @ | 5/6 | = 31/4 |
| 80 ÷ 12 | = | 6·6 | lb. @ | 3/6 | = 23/1 |
| 80 hanks | = | 13·3 | lb. | = 69/5 |
80 ÷ 13·3 = 6·1 counts if twisted, and × 3 = 18·3 counts average.
69/5 ÷ 13·3 = 5/2 per lb. folded.
By computation from the table of prices it is found that
21·4 % of cost is due to silk
45·1 % of cost is due to worsted
33·5 % of cost is due to cotton.
For the weight percentage the proportions are taken from the weight column—
| 1 | 5·7 | |||
| × 100 = 7·52 % silk. | × 100 = 42·8 % worsted. | |||
| 13·3 | 13·3 |
The remaining figure 49·68 % cotton is obtained by subtraction.