Question 594029
Elda walked from her home to her friend Niabi's house at 4.5 km/hr. When Elda returned home along the same route, she strolled at 3.5 km/hr. Elda took a total of 40 min to walk to Niabi's house and back again.
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Avg speed for the round trip = 2*4.5*3.5/(4.5 + 3.5)
= 31.5/8 km/hr
RT distance = r*t = 31.5/8 * (2/3) hr = 21/8 km
--> 21/16 km each way.
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a) How many minutes did Elda take to walk from her home to Niabi's house?
t = d/r = (21/16)/4.5 = 21/72 hours
= 7/24 hours
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b) How far is it from Elda's home to Niabi's house?
--> 21/16 km each way.