An arrangement of 8 students is shown below. The numbers of all the students are in a basket. The teacher selects a number and replaces it. Then the teacher selects a second number. Find each probability.
Row
A 1 2 3 4
B 5 6 7 8
P(student in row A, then student in row B)
since P(A)=P(B) = 1/2, and the drawings are independent,
1/2 * 1/2 = 1/4