#### Answer

$s\geq4p$

#### Work Step by Step

First define your variables
s=# of students
p=# of professors
Now relate the variables to each other by setting them equal
$s=p$
However we know that s does not equal p
In fact the student body is at least 4 times greater
First we will accommodate for the 4 times greater
For both sides of the equation to work out the number of professors must be multiplied by 4 to equal the student body which is 4 times larger
$s=4p$
Last we must accommodate for the at least
The at least tells us that the symbol between both sides of the equation is not an = and is some sort of inequality sign
The problem reads "at least four times as many students as
professors"
Thus the inequality should be a greater than or equal to symbol and open towards s
$s\geq4p$