Exercise 48. Problems of the farmer

1. A farmer raised 42 bushels of corn per acre on 20 acres. The cost per acre of raising the corn was $16.25. He sold the corn for 82¢ a bushel. What per cent did he gain?

2. What per cent of the cost of the corn would the farmer of the preceding problem have made, if he had fed it to hogs, making a gain of 100 pounds for each 9 bushels of corn, and had sold them at $8.75 a hundred pounds?

3. A rectangular corn field is 80 rods long and 40 rods wide. It costs $10 an acre for rent, $1.50 an acre to plow the ground, $1.50 an acre to harrow it, $.40 an acre to plant it, $2 an acre to cultivate it, and $2.40 an acre to husk and haul the corn to the crib. One-half peck of corn at $1.60 a bushel was planted to the acre. What was the total expense of the field of corn? What was the expense per acre?

What

4. The yield per acre of the field of the preceding problem was 46 bushels. The corn was sold at 72¢ a bushel. per cent of profit did the renter make?

5. In an experiment in feeding laying hens two pens of 25 hens each were given the same grain ration. Skim milk was added to the ration in the first pen. The average cost of feed per hen for a year in the first pen was $1.09 and in the other was $.715. The average number of eggs produced by the hens in the first pen was 137 and by the hens in the second pen was 37. The average price received for the eggs was 31.1¢ a dozen. What was the difference in the values of the eggs from the two pens? By what per cent was the value of the eggs produced increased by adding skim milk to the ration? Find the profit from each pen.

6. Seeds should generally be tested before planting. This may be done by planting a number of them in a seed germinator and finding what per cent of the number planted germi

nate. If the vitality of the seed is said to be 95, it means that 95% of the seed planted germinate.

A farmer tests 100 grains of his seed corn and finds that only 65 germinate. What is its vitality? He refuses to plant this seed and buys from a neighbor seed testing 95. His yield of corn from this seed was 47 bushels per acre. What should his yield have been if his seed had had 100% vitality? What should it have been if he had planted his own corn with vitality 65?

7. Clover seed is sometimes of low vitality and also contains weed seed that much resembles clover seed. A farmer finds that his clover seed contains 4% dodder seed. The real clover seed has a vitality of 94. If his seed were pure and had vitality of 100 he would expect a crop of 2 tons per acre. How much may he expect from this seed?

8. When a bushel of Yellow Dent corn on the cob is shelled, the weight of the shelled corn is usually about 88% of the weight of the corn on the cob. The legal weight of a bushel of shelled corn is usually 56 pounds and of a bushel of ear corn 70 pounds. If a bushel of Yellow Dent corn in the ear weighs 70 pounds, how much will the shelled corn from this bushel weigh?

It costs about 14¢ a bushel to have corn shelled. . A farmer has 1200 bushels of Yellow Dent corn in the ear. He can sell it for 85¢ a bushel. Is it better to sell it shelled or in the ear? How much better?

9. If a pasture feeds 2 cows to every 5 acres how much does a thirty-acre pasture earn during a five months' season at $2 a month per cow? How much can be paid for this land so that the buyer may receive an annual income of 6% on the purchase price allowing $1 an acre for expenses?

10. Find the estimated average cost, yield, and profit per acre of the three principal crops in your county.

47. Problems of the dairyman.

Milk as it comes from the cow is called whole milk.

By using a machine called a separator whole milk is separated into cream and skim milk.

A part of whole milk is pure fat, called butter fat, and almost all of this is taken out with the cream by the separator. Butter is the butter fat plus salt, water, and some of the milk. The amount of butter which can be made from a given amount of milk is usually estimated as 14 times the butter fat it contains.

The expression "100 pounds of 4% milk" means that there are 4 pounds of butter fat in the 100 pounds of whole milk. The expression "20 pounds of 25% cream" means that 25% of the 20 pounds of cream is butter fat.

Whole milk is estimated as weighing 2.18 pounds to the quart, and cream as weighing 2 pounds to the quart.

Exercise 49

1. How much butter fat in 800 pounds of 3% milk? In 1275 pounds of 44% milk?

2. The milk of a certain Jersey cow contains 32 pounds of butter fat in 640 pounds of milk. What is the per cent of butter fat?

3. If all the butter fat in 200 pounds of 41% milk is taken out in the cream, how much 25% cream is made?

HINT. The amount of butter fat is 25% of the amount of cream.

4. How much butter can be made from 360 pounds of 5% milk? How much 20% cream?

HINT. See above the relation between butter and butter fat.

5. How much butter fat in 42 pounds of butter?

6. Twenty pounds of cream are taken from 100 pounds of 4% milk and the skim milk is then found to contain .02%

of butter fat. What per cent of the fat is lost in the skim milk?

7. Two neighbors have six dairy cows each. Record is kept of the amount and quality of the milk of each cow as follows:

a. Find the total amount of butter fat for each herd.

b. Find the per cent of butter fat for all the milk of herd No. 1.

c. Find the per cent of butter fat for all the milk of herd No. 2.

Find the value of each herd's product if sold as

d. Butter fat at 32¢ a pound.

e. Butter at 35¢ a pound.

f. Milk at 9¢ a quart.

g. Twenty per cent cream at 40¢ a quart.

h. Find the average annual value of the product per cow of each herd if sold as butter fat at 32¢ a pound.

i. The average cost of feed per cow in herd No. 1 is $62 and in herd No. 2 is $73. How much more than the cost of the feed does each man receive from his herd when the product is sold in each of the above forms? Which cows are not paying for their feed, if butter fat is sold as in h?

Exercise 50. Review

1. Write as per cents: .48, 2.5, 19, .005, &, &, 1, 700, .020. 2. Write as decimal fractions: 27%, .9%, 786%, .03%, 1%, 1.02%, 5%.

7 5 3

3

3. Give the per cent equivalent to each of these: 1, 1, 1, t, t, t, 4, 1, 3, §, b, b, t, b, 12. Practice until these results can be given in 30 seconds or less.

1 7

4. State the formula to be used (a) to find a per cent of a number; (b) to find what per cent one number is of another; (c) to find a number when a certain per cent of it is given. 5. Find .01% of 1.2.

6. $8.40 is 1% of what number?

7. Find 96.84% of $18.72.

8. A yard is what per cent of a meter? 9. 80 is what per cent more than 75? 10. 75 is what per cent less than 80? 11. What number is 20% less than 6? 12. 6 is 20% less than what number?

13. A boy is 4 ft. 2 in. tall. If he increases 5% in height each year for 3 years, how tall will he then be?

14. The estimated wealth of the United States in 1917 was $250,000,000,000. The first Liberty Loan was for $2,000,000,000. The loan was what per cent of the estimated wealth?

15. Find out the present estimated wealth of the United States and the amount of indebtedness. The indebtedness is what per cent of the wealth?

16. A certain steel company earned $6,200,000 on an investment of $17,184,000. The earnings were what per cent of the investment?