Problem: The formula N=8⋅108⋅x−23​ gives, for a certain group, the number of individuals whose income exceeds x​ dollars. The lowest income, in dollars, of the wealthiest 800 individuals is at least:
Answer Choices:
A. 104
B. 106
C. 108
D. 1012
E. 1016
Solution:
We have N=8⋅108⋅x−23​ with N=800; to find x
∴800=8⋅108⋅x−23​,1=106⋅x−23​,x23​=106,x21​=102
x=104