Tourist Walk and Bus

The tourist traveled 78 km in three hours. For part of the journey, he traveled by bus at an average speed of 30 km/h, and for the rest, he walked at an average speed of 6 km/h. How long did he walk, and how many kilometers did he walk?

Final Answer:

b =  2.5 h
s =  3 km

Step-by-step explanation:

30a + 6b = 78
a+b = 3

30·a + 6·b = 78
a+b = 3

30a+6b = 78
a+b = 3

Row 2 - 1/30 · Row 1 → Row 2
30a+6b = 78
0.8b = 0.4


b = 0.4/0.8 = 0.5
a = 78-6b/30 = 78-6 · 0.5/30 = 2.5

a = 5/2 = 2.5
b = 1/2 = 0.5

Our linear equations calculator calculates it.

$s=6\cdot b=6\cdot 0.5=3\text{km}$

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