1. A farmer built a cylindrical silo 10 feet in diameter and 20 feet high, inside measurements. If a cubic foot of silage (green corn fodder) weighs 36 pounds, how many tons are there in the silo when it is full?

2. A silo 32 ft. high and 16 ft. in diameter is full of silage. If 50 cu. ft. of silage weigh a ton, and a cow eats 30 lb. of it in a day, how long will this silage last 50 cows?

3. To keep silage in good condition a layer 2 inches deep should be used daily. A silo is 12 feet in diameter and is filled to such a depth that a cubic foot of silage weighs 35 pounds. How many cows should be kept to feed a layer 2 inches deep every day if each cow needs 34 pounds daily? Call 22.

4. The farmer who owns the silo in the previous problem wishes to keep enough cows to lower the silage in the silo 3 inches daily. How many must he keep?

Compute the area of each of the figures within this rectangle. What % of the large rectangle is the sum of the areas of the figures within it?

COMPUTING THE AREA OF IRREGULAR FIGURES

1. Find the area of a field in the shape of a polygon ABCDE, if AC=610 yd.; EF = 140 yd.; HD=220 yd.; BG =230 yd.; AF = 100 yd.; AG =260 yd.; and AH =460 yd.

2. The two parallel sides of a field are 120 rd. and 84 rd., and its width is 40 rd.

100 yd.

B

N

120

160 yd.

C

D

160 yd.

160 yd.

E

W

F

160 yd.

230 yd.

H

230 yd.

I

E

Find the area in acres.

3. A line NS, running north and south, is the boundary line between the farms of S. C. Brown and C. L. Smith. In order that each party may have all of his land on one side of the stream, it was agreed that Brown should sell to Smith all the land Brown owned inside of the south bend of the river and Smith should sell to Brown all the land Smith owned inside of the north bend of the river, the price to be $100.00 per acre in each case. The surveyor set stakes at A, B, C, D, E, F, G, H, I, and J, 100 yd. apart, and measured the distance from each point to the river on a line at right angles to NS, as indicated in the diagram. It was agreed that the oblique side of each triangle or polygon so made should be considered a straight line from point to point. Which party is to make a cash payment in the transfer and how much?

BROWN

8

G

J

In some villages each residence has its own well or cistern; in others there is a well at the public square or elsewhere for all the people; in others there is a large reservoir from which the water is piped to each home or business place. The last method is the one used by villages and cities with modern conveniences.

1. What is meant by modern conveniences?

2. State several reasons why the last method is most desirable?

Some cities are so situated that they must draw their water supply from a nearby stream or lake. This requires that the impurities be removed by settling or filtering, or by both, before the water is fit for use.

Name several impurities that should be removed.

WATER SUPPLY PROBLEMS

91

1. A certain village in Ohio has in round numbers a population of 500. The reservoir for the town supply is a cylindrical tank 36 ft. long with a 9-foot diameter. What is the capacity of the reservoir? Count 7 gal. to the cu. ft.

2. The pump which supplies the tank in the first problem throws 2.7 gal. to the stroke and makes 23 strokes to the minute. How long, with steady pumping, will it require to fill the tank?

3. If the pump is driven on an average of 8 hours daily, how many gallons of water are allowed daily to each inhabitant in the village of problem one?

4. In a city whose population is 750,000, the cost of purifying its water in 1918 was $7.37 per million gallons. How much was that per gallon? At this rate how many gallons were purified for one cent?

5. In the same city the average daily consumption for 1917 was 104.3 million gallons. How much was that daily per person? How much was the total consumption for 1917? Express your answer in millions.

6. Using the data in 4 and 5, determine the average cost of purifying the water used by each person in a year.

7. St. Louis yearly purifies 36 billion gallons of water by adding 5.35 grains of lime, .68 grains of iron sulphate (copperas), and .58 grains aluminum sulphate (alum) to each gallon. How many tons of each of these materials are used yearly?