Line B per minute: 30 kilometers divided by 60= 1/2 kilometers per minute.

A: 30 minutes is enough: 30*2/3=20 kilometers.

Solution: See you in X minutes after the armor is repaired.

(2/3+ 1/2)X+ 15 * 1/2 = 150-20

7/6X +7.5 = 130

7/6X = 130-7.5

X= 105

Departure b:105+15 =120 (minutes) =2 hours.

A: B will meet A two hours after takeoff.