Question 854666: A runs at 07:00 a.m. With a speed of 10 km/hr.After 2 hrs,B runs with a speed of 20 km/hr, then find when they will meet together. Answer by josmiceli(19441) (Show Source):
You can put this solution on YOUR website! How far does A get in 2 hrs? km
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Start a stopwatch when B leaves
Let = time in hrs when they meet
Let = the distance in km that B runs
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A's equation:
(1)
B's equation:
(2)
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Substitute (2) into (1)
(1)
(1)
(1)
They will meet 2 hrs after B leaves,
which is 7:00 + 2 hrs + 2 hrs = 11:00 AM
check:
(1)
(1)
(1)
and
(2)
(2)
(2)
OK
