108 FARM ARITHMETIC. 



per acre, how many bushels of increase would there be 

 with the same acreage as in 1909 ? 



334. When sold at 80 cents per bushel what would be 

 the value of the increased production? 



335. An ideal country road may be graded and made 

 of stone for a sum not exceeding $3,000 per mile. How 

 many miles of such road could be made annually from the 

 sum represented by one bushel per acre increase in the 

 wheat crop? 



336. How many such roads from Boston to San Fran- 

 cisco might thus be built each year ? 



337. How many years would be required to pay in this 

 way for such a road, whose length is equal to the circum- 

 ference of the earth ? 



338. Corn is often calculated on a basis of 120 ears 

 per bushel. What is the weight of each ear? 



339. When corn is planted in rows 44 inches apart, 

 how many rows per acre in a field SO rods long? 



340. How many stalks per acre when planted 12 

 inches apart in the row ? 



341. When one ear is produced per stalk, what is the 

 yield per acre? 



342. If corn is selected and bred to average one and 

 one-half ears per stalk of same weight as above, what is 

 the yield per acre? 



343. If corn is bred so as to increase the weight — 100 

 ears to the bushel — what will be the yield per acre, corn 

 being planted 12 inches apart in rows 44 inches wide ? 



344. If corn is planted 12 inches apart in rows 38 

 inches apart, what is yield per acre, one ear per stalk 

 and 120 ears per bushel? 



