Boat A Wins by 40 Minutes: Solving a Boat Race Across a 70-km Lake

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Boat A completes the 70-km round trip in 2 hours, while Boat B takes 2 hours and 40 minutes, resulting in Boat A winning by 40 minutes. The calculations show that Boat A travels at a consistent speed of 70 km/h, while Boat B's speed varies, impacting its total time. A participant struggles with entering the correct distance for Boat A, mistakenly truncating the decimal instead of rounding it properly. The correct rounding of 46.6666... should be either 46.67, 46.7, or 47, depending on significant figures. Proper rounding is crucial for accurate homework submissions.
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Homework Statement


Two boats start together and race across a 70-km-wide lake and back. Boat A goes across at 70 km/h and returns at 70 km/h. Boat B goes across at 35 km/h, and its crew, realizing how far behind it is getting, returns at 105 km/h. Turnaround times are negligible, and the boat that completes the round trip first wins.

Boat A wins but by how much?

The Attempt at a Solution



So I entered into a velocity calculator to determine that it would take Boat A 2hours to finish the course while it would take Boat B 2hrs 40 min to complete the course or simply put boat A wins by 40min

70kmh at 40 minutes would travel 46.667km and yet when I enter the answer for my online homework thingy it says it wrong even when I enter it as 46, 46.6,46.66, and 46.667

What am I missing hear?
 
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carrollk9 said:

Homework Statement


Two boats start together and race across a 70-km-wide lake and back. Boat A goes across at 70 km/h and returns at 70 km/h. Boat B goes across at 35 km/h, and its crew, realizing how far behind it is getting, returns at 105 km/h. Turnaround times are negligible, and the boat that completes the round trip first wins.

Boat A wins but by how much?

The Attempt at a Solution



So I entered into a velocity calculator to determine that it would take Boat A 2hours to finish the course while it would take Boat B 2hrs 40 min to complete the course or simply put boat A wins by 40min

70kmh at 40 minutes would travel 46.667km and yet when I enter the answer for my online homework thingy it says it wrong even when I enter it as 46, 46.6,46.66, and 46.667

What am I missing hear?
Well, you are not rounding 46.666666... correctly, for one thing. Instead of rounding, you are truncating the decimal by chopping off the extra digits.

46.6666... would be either 46.67, 46.7, or just 47, depending on how many sig figs you wish to carry.
 
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