Carly is training for a triathlon. In her training routine each week, she runs 7 times as far as she swims, and bikes 3 times as far as she runs. One week she trained a total of 232. How far did she run that week?

Respuesta :

Answer: [tex]56[/tex]

Step-by-step explanation:

Let be "s" the distance Carly swam that week, "b" the distance Carly bikes and "r" the distance Carly ran that week.

According to the exercise:

[tex]s+b+r=232[/tex]     [Equation 1]

We know that she runs 7 times as far as she swims; then:

[tex]r=7s[/tex]       [Equation 2]

Since she bikes 3 times as far as she runs:

[tex]b=3r[/tex]      [Equation 3]

The steps to solve this are:

- Solve for "s" from the [Equation 2]:

[tex]r=7s\\\\s=\frac{r}{7}[/tex]

- Substitute this into [Equation 1].

- Substitute [Equation 3] into [Equation 1].

Then:

[tex]\frac{r}{7}+3r+r=232[/tex]

- Solve for "r":

[tex]\frac{r}{7}+3r+r=232\\\\r(\frac{1}{7}+3+1)=232\\\\\frac{29}{7}r=232\\\\r=(232)(\frac{7}{29})\\\\r=56[/tex]