at noon two planes leave at 3,377mi apart and are coming toward each other at a parallel line if one travels at 610mph and the other 618mph how long will it take to reach each other

recall that speed is distance travelled per unit time, or

v = d/t
since they are travelling towards each other, we add their speeds (since travelling towards each other consumes less time for them to meet than travelling in the same direction)
substituting,
v = d/t
610 + 618 = 3377/t
1228 = 3377/t
1228*t = 3377
t = 3377/1228
t = 2.75 hours

hope this helps~ :)