How long will it take them before both cars reach the starting point again simultaneously?
jaymie asked:
Cory and Melissa are racing electronic cars around a circular track. They begin at the same time going in the same direction. Cory’s car completes a revolution in 40 seconds, while Melissa’s car completes a revolution in 35 seconds. How long will it take them before both cars reach the starting point again simultaneously?
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Cory and Melissa are racing electronic cars around a circular track. They begin at the same time going in the same direction. Cory’s car completes a revolution in 40 seconds, while Melissa’s car completes a revolution in 35 seconds. How long will it take them before both cars reach the starting point again simultaneously?
December 17th, 2009 at 11:02 pm
the least common multiple of 35 and 40 is 280
it will take 280 seconds, or 4 minutes and 40 seconds
to check, Cory’s car will go around exactly 7 times
Melissa’s will go around exactly 8 times
please vote best answer:) Me
December 18th, 2009 at 7:32 am
In 280 seconds, Melissa’s car will have completed 8 laps, and Cory’s car will have completed 7 laps. The Gnostic
December 20th, 2009 at 4:26 pm
It would take 280 seconds or eight laps around the track. Missy R
December 21st, 2009 at 12:34 am
lcm of 35 and 40 = 280
after 280 seconds Moise Gunen
December 21st, 2009 at 11:11 am
That’s really just a mental problem.
Difference per lap = 5s.
Melissa does a lap in 35 secs.
35/5 = 7 laps by Corey to 8 by Melissa.
8 x 35 = 280 secs. Technobuff