Final answer:
To estimate the number of students expected to receive $250 or more, we need to add the number of students within each quartile. Based on the information provided, an estimated 150 students are expected to receive $250 or more.
Step-by-step explanation:
In order to determine how many students are expected to receive $250 or more, we need to find the number of students within the first, second, and third quartiles and add them together. The first quartile (25% of students) is $250, the second quartile (50% of students) is $700, and the third quartile (75% of students) is $1,200. So, we can estimate that a total of 150 students will receive $250 or more.