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Yuto left his house at 10 a.m. to go for a bike ride. By the time Yuto’s sister Riko left their house, Yuto was already 5.25 miles along the path they both took. If Yuto’s average speed was 0.25 miles per minute and Riko’s average speed was 0.35 miles per minute, over what time period in minutes, t, starting from when Riko left the house, will Riko be behind her brother?

2 Answers

5 votes

Answer:

The solution means that Riko will be behind Yuto from the time she leaves the house, which corresponds to t = 0, until the time she catches up to Yuko after 52.5 minutes, which corresponds to t = 52.5. The reason that t cannot be less than zero is because it represents time, and time cannot be negative.

Hope this helps!!! :) Have a great day/night.

User Borislav Sabev
by
5.3k points
5 votes

Answer:

52 minutes and 30 seconds

Explanation:

You know that Yuto has ridden for 5.25 miles when Riko left their house and you need to know and what time they will be together:

Then you can say that:

5.25 miles+(yutos speed)*t= (Rikos speed)*t

when t=Time in minutes when they will be together

5.25 miles+(0.25miles/min)*t= (0,35miles/min)*t

5.25miles=(0.35miles/min-0.25miles/min)*t

5.25miles/(0.35miles/min-0.25miles/min)=t

t=52.5 min =52 minutes and 30 seconds

User TXK
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5.2k points