30 



MULTIPLE PURPOSE RIVER DEVELOPMENT 



water input. Heavier rates of water use would be superfluous and 

 would begin to reduce total output. 



Thus far, we have dealt with purely physical relationships in 

 which different technical means were considered for producing a 

 given quantity of output. The particular choice of means — in our 

 illustration, the choice of factor proportions in achieving a given 

 output — is an economic problem. Given the prices of the two 

 factors, just used in the illustration, the most efficient combination 

 would be one which produced the maximum output for a given 

 outlay. The conditions which would have to be met to achieve 



FIGURE 6. The Producer's Choice of Efficient Factor Proportions 



