We can use the following formulas to find the price of Stock A and Stock B at different times:
Price of Stock A at time t = 12.91 + 0.13 * t
Price of Stock B at time t = 13.66 - 0.09 * t
To find the time at which the prices of the two stocks are equal, we can set the two formulas equal to each other and solve for t:
12.91 + 0.13 * t = 13.66 - 0.09 * t
0.24 * t = 0.75
t = 3.125
Since the two rates are given in hours, t must be expressed in hours. Since 3.125 is not a whole number of hours, we can round it up to the next whole number of hours, which is 4 hours. Therefore, it will take 4 hours for the prices of the two stocks to be the same.