EXERCISE 93 



WHAT IS THE RELATION BETWEEN THE WEIGHT OF THE GRAINS AND THAT OF 



THE COB IN EARS OF CORN? 



Materials. Same as in Exercises 91 and 92. 



Directions. Weigh the ear. Shell the grains from the cob. Be careful to lose none. Weigh the 

 grains and record the weight, using the blanks given below. Weigh the cob. Add the two weights, 

 and if they do not correspond with the total weight of the ear (Exercise 92), try to discover your 

 error. 



Place the weights of grains and cob on the board at the sides of the corresponding figures for 

 each ear. Underline the ear having the largest weight of grains ; largest weight of cob ; smallest 

 weight of grains ; smallest weight of cob. 



Additional problems. What percentage of the total weight of the ear is the weight of the grains ? 

 Record this percentage at the side of corresponding numbers for the ear. Underline the highest and the 

 lowest percentage of grains to total weight. In the light of all facts shown, which ear would you now 

 select as the best for planting ? 



Could you select from the above data any combination of characteristics which would appear better 

 than any combination which was found ? 



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