Answer:
7:12 a.m
Step-by-step explanation:
Given that:
Train to New York city leaves station every 7 minutes
Train to Boston leaves station every 6 minutes
Current time = 6:30 a.m
Time both will leave station together is obtained by finding the least common multiple of 6 and 7
Multiples of ;
6 = 6, 12, 18, 24, 30, 36, 42, 48, 54, 60,...
7 = 7, 14, 21, 28, 35, 42, 49, 56, 63, 70,...
The least common multiple of 6 and 7 is 42.
Hence, both trains will leave the station together after 42 minutes ;
Current time + 42 minutes
6:30 a.m+ 42 minutes = 7:12 a.m