Question

Hong swam kilometers against the current in the same amount of time it took him to swim kilometers 16 with the current. The rate of the current was 1 kilometer per hour. How fast would Hong swim if there were no current?

Answer 1

3 kilometers per hour

Explanation:

Please consider the complete question.

Hong swam 8 kilometers against the current in the same amount of time it took him to swim kilometers 16 with the current. The rate of the current was 1 kilometer per hour. How fast would Hong swim if there were no current?

Let x represent Hang's swimming rate.

Hang's rate upstream would be:
`x-1`

Hang's rate downstream would be:
`x+1`

`\text{Time}=\frac{\text{Distance}}{\text{Rate}}`

`\text{Time taken downstream}=(16)/(x+1)`

`\text{Time taken against current}=(8)/(x-1)`

Since downstream and upstream times are equal, so we can equate both equation as:

`(16)/(x+1)=(8)/(x-1)`

Cross multiply:

`16(x-1)=8(x+1)`

`16x-16=8x+8`

`16x-8x-16=8x-8x+8`

`8x-16=8`

`8x-16+16=8+16`

`8x=24\\\\(8x)/(8)=(24)/(8)\\\\x=3`

Therefore, Hong would swim at a rate of 3 kilometers per hour, if there were no current.