Four different electronic devices make a beep after every 30 minutes, 1 hour, 112 hour and 1 hour 45 minutes respectively. All the devices beeped together at 12 noon. They will again beep together at :(a) 12 midnight(b) 3 a.m.(c) 6 a.m.(d) 9 a.m.

Harshit Singh , 3 Years ago

Grade 12th pass