Solution: 
-l4- 
1. According to the properties of the well known Bell curve, an 
error of 0.02 in. in 90$ of the points correspond to a mean 
square error of 0.02/1.64 = 0.0120 in. or, in other words: 
jJL-J = 0.012 in. 
Hr = 
Mp* + m p 2+ H-Pgc 
w 
h 
a 
E 
0.20 ZoZ 
(5) 
~ 1000 (^7000) 5.4 
ITip = 0.0026 in. , measured on the publication 
scale of the map (l: 25000). 
Since the ground control is to be considered error-free 
in this example, we have: ^ 
S c 
Thus 
, ¡JLp - 0.0117! in. 
tn 
In the case of a strip, 4p - M' » 
thus, f~i - 0.01171 in. 
3. mbd (feet) = 0-43B \ 44 > 
\ f~-Lo z 
here we have: 
of 4^— (27000 ft.) = 117 82 ft. 
o. ciò ih. J 
= 0.01171 in. 
M-o = - 0.01 mm. = ± 0.00039 in. 
Z = H = 27000 ft. 
f = 8.25 in. 
S = 25000