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ruslelena [56]
3 years ago
15

Fiora starts riding her bike at 20 mi/h. after a while, she slows down to 12 mi/h, and maintains that speed for the rest of the

trip. the whole trip of 70 mi takes her 4.5 h. for what distance did she travel at 20 mi/h?
Physics
2 answers:
hammer [34]3 years ago
3 0
<span>d = r*t

t = hours at 20 mi/hr


20t + 12*(4.5 - t) = 70
8t = 16
t = 2 hours

d at 20 mi/hr = 20*2 = 40 miles

40/20 + 30/12 = 4.5 hours

Fiora travels a total distance of 4.5 hours</span>
Nezavi [6.7K]3 years ago
3 0

Answer : Distance, d = 40 mi.

Explanation :

It is given that,

Fiora starts riding her bike at 20 mi/h. after a while, she slows down to 12 mi/h and maintains that speed for the rest of the trip. the whole trip of 70 mi takes her 4.5 h.

Let for t hours she traveled at 20 mi/h. So, for ( 4.5 - t) h she has traveled with a speed of 12 mi/h.

We know that,

distance covered = speed × time

20 mi/h × t +12 mi/h (4.5 h - t) = 70 mi

t = 2 h

So, the distance covered in 2 h is, d = 20 mi/h × 2 h = 40 mi.

Hence, this is the required solution.

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