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A runner is jogging in a straight line at a steady Vr= 3.4km/hr. When the runner is L=8km from the finish line, a bird begins flying straight from the runner to the finish line at Vb= 17km/hr(5 times as fast as the runner). When the bird reaches the finish line, it turns around and flies directly back to the runner. What cumulative distance does the bird travel?

1 Answer

2 votes

Answer:

The cumulative distance that the bird travel is 13.33 Km

Step-by-step explanation:

Given that,

Velocity of runner = 3.4 km/hr

Distance = 8 km

Velocity of bird = 17 km/hr

Let x is the distance from the origin where the runner run into the bird

We need to calculate the value of x

Using time of runner and bird


t_(r)=t_(b)


(d_(r))/(v_(r))=(d_(b))/(v_(b))

Put the value into the formula


(x)/(3.4)=(8+(8-x))/(17)


17x=3.4*8+3.4(8-x)


17x=27.2+27.2-3.4x


17x+3.4x=54.4


x=(54.4)/(20.4)


x=2.67

We need to calculate the cumulative distance that the bird travel

Using distance of bird


d_(b)=16-x

Put the value into the formula


d_(b)=16-2.67


d_(b)=13.33\ km

Hence, The cumulative distance that the bird travel is 13.33 Km

User Graney
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