Answer:
$0.33 per inch
Step-by-step explanation:
Divide cost by inch to get cost per inch.
We must assume that all workmen work at the same rate, and keep it up forever.
More men ==> fewer days
so the proportion is: 30/25 = x/10
Cross-multiply the proportion:
300 = 25 x
Divide each side by 25 :
x = 300/25 = <u>12 men</u>