Ram and shyam going to goa from delhi @15 and 12 km per hour respectively after half hour and hour meena also starts the journey and crosses shyam in some time further on in 90 mins she cross ram find speed of means
Answers
Answer:
speed of Meera is 47 km/hour.
Step-by-step explanation:
Let Meera speed is x km/s.
Let Meera meet Shyam at t hours.
At the time of meeting, distance traveled by both are same.
Distance traveled by Shyam = Distance traveled by Meera
from Distance = speed x time, we can derive.
(Speed of Shyam = 12 km/h)
12t = x(t - 0.5) (Since Meera started half an hour late)
2(12 - x)t + x = 0
t = x/2(x - 12) ---------------E1
After 90 minutes, Meera and Radha met.
Distance traveled by Radha = Distance traveled by Meera
15(t + 3/2) = x(t + 3/2 - 0.5)
15(t + 3/2) = x (t + 1)
15(2t + 3) = 2x(t + 1)
30t + 45 = 2xt + 2
-43 = (30 - 2x)t
t = 43 / (2x - 30) -----------E2.
Equating E1 and E2, we get
x/(2(x - 12) = 43 / (2x - 30)
x(2x - 30) = 86(x - 12)
2x² -116x + 1032 = 0
x² - 58x + 516 = 0
Solving x we get x = 47.0 and 10.9.
Since speed of Meera can not be less than other two. We ignore 10.9.
Hence speed of Meera is 47 km/hour.