The mean equated lengths are as follows:—
| Line I H. D to G. | Mean, 79.46, | ||
| 61.14 + | 1187 96 + 7609 1140 = 61.14 + | 12.36 + 6.68 = 80.18 | |
| Line I H. G to D. | |||
| 61.14 + | 1049 96 + 7609 1140 = 61.14 + | 10.93 + 6.68 = 78.75 | |
| Line E F. D to G. | Mean, 66.56. | ||
| 58.53 + | 454 96 + 4588 1140 = 58.53 + | 4.73 + 4.02 = 67.28 | |
| Line E F. G to D. | |||
| 58.53 + | 316 96 + 4588 1140 = 58.53 + | 3.29 + 4.02 = 65.84 | |
The comparison as to cost is
I H to E F as $1,094,950 to $1,496,430,
and as to working,
I H to E F as (79.46 × 4000) × 100
6 to (66.56 × 4000) × 100
6,
and the sum as
| 1,094,950 | to | 1,496,430 | |
| + 5,297,334 | + 4,437,334 | ||
| or | $6,392,284 | to | $5,933,764 |
Although the cost of E F is $401,480 more than that of I H, the line E F was adopted.