3. An electronic flea can jump from one circle to an adjacent circle with each step. Now, a red flea starts from the circle marked with the number "0" and jumps 1991 steps in a clockwise direction, landing in one circle. A black flea also starts from the circle marked with the number "0", but it jumps 1949 steps in a counterclockwise direction, landing in another circle. What is the product of the numbers in these two circles?
3. 【Solution】The electronic flea returns to its original position every 12 steps.
Since $1991=165 \times 12+11$
the red flea, starting from the circle marked with the number “0”, jumps 1991 steps in a clockwise direction and lands on the circle marked with the number “11”.

Similarly, since $1949=162 \times 12+5$, the black flea, starting from the circle marked with the number “0”, jumps 162 sets of 12 steps in a counterclockwise direction and lands on the circle marked with the number “7”. Therefore, the required product is $11 \times 7=77$.
Answer: The product is 77.