7.15 am (option C)
Step-by-step explanation:
Time bus begin their routes = 6.00am
Time it takes Bus A to laeve = 75 minutes
Time it takes bus B to leave = 15 minutes
We need to find the lowest common multiple of both times
15 = 3 × 5
75 = 3 × 5 × 5
LCM = 3 × 5 × 5 = 75
The time bus A and B will leave the bus station both times = time it begins + the LCM
The time bus A and B will leave the bus station both times = 6.00am + 75 minutes
75 minutes in hours:
1 hour = 60 minues
75 minutes = 60 minutes + 15 minutes = 1 hour 15 minutes
The time bus A and B will leave the bus station both times = 6.00am + 1 hour 15 minutes
The time bus A and B will leave the bus station both times = 7.00am + 15 minutes
The time bus A and B will leave the bus station both times = 7.15 am (option C)