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That this course may be of the largest value to mechanics, contractors, and others whose school training has been limited, it is necessary to begin with a thorough course in industrial arithmetic. Upon no other educational foundation can you expect to build intelligent and satisfactory bids and estimates. The work begins very easy. You should do every exercise. The answers, with hints for solution whenever necessary, are given at the end of the


Lesson No. 1. Simple Linear Measurements


320 rods = 1 mile 1760 yards 1 mile 16 feet = 1 rod



1. Find the cost of 20 mi. of wire at 35¢ a pound, supposing that 1 lb. stretches 50 ft.

2. What is the cost of a cable 921 ft. long at 95¢ a yard? 3. A township is 6 mi. square. Find the cost of fencing it at 65¢ a rod.

4. How many inches are there in 131⁄2 rd. ?

5. A city is laid out in squares, each of which measures one-eighth of a mile from the center of the street crossing


to the center of the next street crossing. Find the cost of laying water pipes along the streets, as shown by the dotted lines in the diagram, at an expense of $ 1.15 per foot.

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1. How many yards are there in 24 ch.?

2. Find the distance in yards around a field 24 ch. long

by 28 rd. wide.

3. How many chains in 20,460 ft.?

4. A surveyor reports the length of a projected railway as 6560 ch. What will it cost to build the road at an estimate of $20,000 a mile?

5. The above drawing represents a Dakota township, and the shaded portion a wheat farm belonging to one man. The township is 6 mi. square. Find the total cost of fencing in the farm, as per the lines in the drawing, at $5.70 per chain.

Lesson No. 3. Simple Square Measurements


144 square inches = a square foot.
9 square feet = a square yard.

RULE: To find the area of any rectangle, that is, any foursided figure the corners of which are right angles, — multiply the length by the breadth. Before multiplying you must have the length and breadth both in the same denomination. If both are inches, the answer will be square inches; if both are feet, the answer will be square feet; and so on.

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