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3 years ago

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A remote-controlled boat traveled 18 feet heading west and 24 feet heading south, totaling 42 feet over the course of 10 seconds

. Heading west, the boat traveled at an average speed of 3 feet per seconds less than its speed heading south. What was the average speed of the boat heading west? (Do not include the units in your response.)

1 answer:

Dominik [7]3 years ago

3 0

Answer:

3 ft/s

Explanation:

given,

distance in west, d₁ = 18 ft

distance in south, d₂ = 24 ft

time taken to travel 42 ft = 10 s

speed of boat in north = x ft/s

Speed of the boat when heading west = (x - 3) ft/s

$Average\ speed = \dfrac{total\ distance}{total\ time}$

$v_{avg}= \dfrac{42}{10}$

$v_{avg}= 4.2\ ft/s$

again using the above formula

now, total time

t = t₁ + t₂

$10 = \dfrac{18}{x-3} + \dfrac{24}{x}$

on simplifying

10 x² -72 x + 72 = 0

On solving the above equation we get

x = 6 ft/s

Hence, speed of boat in west direction, 6 -3 = 3 ft/s

speed of boat in south direction = 6 ft/s

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