Instead of riding a tricycle, Nilda walks from her house to school after she learned that walking is good for the health. If the time in walking the distance from the house to school at 4kph is 30min longer than what is required at 5kph when taking a tricycle, find this distance ... Solution plss...

distance is velocity times time
d = vt
when riding tricycle:
d = 5t ---equation 1
(5kph is the velocity, t is the time)
when walking
d = 4 (t + 0.5) ----equation 2
(4 is the velocity, 't+0.5' is the time')
equating equation 1 and 2
5t = 4(t+0.5)
5t = 4t + 2
5t - 4t = 2
t = 2hours
substitute t=2 to equation 1
d = 5kph(2hours)
d = 10km

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