Question

The English Channel is the waterway between England and France. It is about 21 kilometers across, and many people have successfully swam across it. In the United States, many pools at gyms are 25 yards long, and 1 lap equals the pool length.Assuming a person swims in a straight line, how can you calculate the number of complete laps a person must swim in a 25-yard pool to equal swimming across the English Channel?A) First, convert the distance across the channel to approximately 13 miles. Next, convert the distance in miles to 22,880 feet. Then, convert the pool length to 75 feet. Finally, multiply the distance by 1 lap 75 ft. to get about 305 laps.B) First, convert the distance across the channel to approximately 34 miles. Next, convert the distance in miles to 179,520 feet. Then, convert the distance in feet to 59,840 yards. Finally, multiply the distance by 1 lap 25 yd. to get about 2,394 laps.C) First, convert the distance across the channel to approximately 34 miles. Next, convert the distance in miles to 59,840 feet. Then, convert the pool length to 75 feet. Finally, multiply the distance by 1 lap 75 ft. to get about 798 lapsD) First, convert the distance across the channel to approximately 13 miles. Next, convert the distance in miles to 68,640 feet. Then, convert the distance in feet to 22,880 yards. Finally, multiply the distance by 1 lap 25 yd. to get about 915 laps.

Answer 1

The first step to find the correct answer indeed is to convert the distance across the channel from kilometers to miles.

Because 1 km is equal to approximately 0.62 miles, 21 kilometers will be just 21 times the 0.62 miles. From this, we are able to calculate the following:

From this, we are able to say that the correct answer is not B or C.

Now, because 1 mi is equal to 5,280 ft, we can say that 13 mi is equal to 13 times 5,280 ft. From this, we calculate:

`\begin{gathered} 13mi=13*5,280ft \\ 13mi=68,640ft \end{gathered}`

From this, we are able to say that the correct answer is not A also. To convert it to yards, we need to remember that 1 foot is equal to (1/3) yards, which means that 68,640 ft is equal to 68,640 times (1/3) yards. Calculating, we get the following:

`\begin{gathered} 68,640ft=68,640*(1)/(3)yd \\ 68,640ft=22,880yd \end{gathered}`

Because the lap in the pool is 25 yd, we need to DIVIDE, not to multiply, the distance of the channel in yards we found by the distance of the pool, which is 25 yd.

From this, we get the following answer:

`N_{of\text{ laps}}=(22,880yd)/(25(yd)/(lap))=915.2\text{ laps}`

From this, we know that the number of laps a person who wants to swim the same distance of the channel mentioned is equal to approximately 915 laps

And the final answer is D.