Baking 1 tray of cookies started from 18:15 to 19:39. Calculate how long, in minutes, it took to bake a tray of cookies. Maths literacy?

To calculate the time it took to bake a tray of cookies, we need to find the difference between the starting time (18:15) and the ending time (19:39).

First, convert both times to minutes:
18:15 = 18 x 60 + 15 = 1095 minutes
19:39 = 19 x 60 + 39 = 1179 minutes

Now, subtract the starting time from the ending time:
1179 - 1095 = 84 minutes

Therefore, it took 84 minutes to bake a tray of cookies.