We are given that
Good stuff is giving away pens to each of the first 200 peopel who come in the store today
so, total number of people given is

In the first hour, they gave 75% of the pens
so, we need to find total number of pens given in first hours
percentage of pens given 1st hour =75%
so,
total number of pens given in first hour = (percentage of pens given 1st hour)*(total number of people given)
now, we can plug values
and we get
total number of pens given in first hour is


................Answer