(9.6) 



X = 



where a, b, and c determine the coefficients of the unknown tilted refer- 

 ence plans. 



The equation for the leveled data is 



N^=Nj^-aj-;-,k.c 

 The modified equations which take into account the missing data are given 

 by eqn. (9. 7) where the summations omit the missing points. 

 (9.7) A'X = B" 



The numerical results for sets 2 and 3 are as follows: 



A' 



B' 



X 



Set 2 



/ 



6,312,334 7,081,560 

 7,081,560 14,329,800 

 \ 159, 138 240, 120 



/ 767,640.680\ 

 1, 184,012.640 

 26,618.730 



/ -.010744 \ 



-.000140 

 \ +5.256144 / 



Set 3 



159, 138 \ /6, 307, 157 7,072,663 159,033' 



240, 120 I 7,072,663 14,313,780 239,892 



5,396/ \ 159,033 239,892 5,393 



/ 847,416.000 \ 

 1,261,367.290 

 28,650.330 / 



/ + .001575 



-.003584 



\ +5.425500 



84 



