Question 898386
The function P(x) = 90-25log base2(x)  models the percentage P(x) of students who would recall the important features of a classroom lecture as a function of of time where x represents the number of days that have elapsed since the lecture was given.  Let P(x) = 50 and solve for x.
After how many days do only half of the students recall the important features of the classroom lecture?
---------------------
P(x) = 90-25log2(x) 
50 = 90-25log2(x)
-25log2(x) = -40
log2(x) = 8/5
x = 2^(8/5)
x = 3.03 days
==================

Cheers,
Stan H.
----------------