Question

E^x/2.9099=ln 7.8x10^10

Answer 1

I interpreted your question this way:

e^(x/2.9099) =ln (7.8x10^10)
take ln of both sides , so we taking ln (ln(...)) on the right side

x/2.9099 = ln (ln (7.8 x 10^10) )
x/2.9099 = 3.22207
x = 9.3759...