What is the Solution to the Equation with 8 and 1?

[espania]

http://www.comlab.hut.fi/opetus/610/exercises_fall2004/T2_sol_041119.pdf

Where did he get the 8 from? And what is with the number 1? In the first solution.

 

[HallsofIvy]

Where is this from? That looks like a not-very-good translation into English from another language. The final question should be "How fast did he have to be going in order for his claim to be true?", NOT "How quickly he had to move in order his claim to be true."! Of course my (whatever was the original language) is non-existant so I can't complain.

There is clearly a problem with the PDF conversion (unfortunately, Adobe is not perfect and if this was originally done in some other language, there may have been non-standard characters used that Adobe did not recognize.)

I'm not certain what was supposed to be there but I do note that 630/560 = 1.125, 1 and 1/8 so that 1/8= 630/560- 1.

Perhaps the formula was intended to be
$$\frac{l}{l'}= 1-\frac{v}{c}$$

Then
$$\frac{v}{c}= 1- \frac{l}{l'}$$
which, with the values given would be 1/8.

 

[thepatientmental]

The solution to the equation with 8 and 1 is not clear without more context. It is possible that the author is referring to a specific mathematical problem that involves the numbers 8 and 1. In this case, the solution would depend on the specific equation and cannot be determined without more information. It is also possible that the author is using 8 and 1 as variables in a general equation, in which case the solution would depend on the values assigned to those variables. Without more context, it is not possible to provide a definitive answer.