John runs a marathon (26.2 miles) in 4 hours. Determine how many miles he runs per hour if the proportional relationship is represented by 4y=26.2x

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1 answer

To determine how many miles John runs per hour, we can use the given proportional relationship represented by the equation \( 4y = 26.2x \).

In this equation, let:

  • \( y \) represent the number of hours,
  • \( x \) represent the distance in miles.

Since John runs the marathon in 4 hours, we can substitute \( y = 4 \) into the equation:

\[ 4(4) = 26.2x \]

Now simplify the left side:

\[ 16 = 26.2x \]

Next, we solve for \( x \) by dividing both sides of the equation by 26.2:

\[ x = \frac{16}{26.2} \]

Calculating the fraction:

\[ x \approx 0.6091 \]

This means that John runs approximately \( 0.6091 \) miles in 1 hour.

To find the exact miles per hour he runs, we can also calculate the average speed directly:

\[ \text{Miles per hour} = \frac{\text{Total miles}}{\text{Total hours}} = \frac{26.2 \text{ miles}}{4 \text{ hours}} = 6.55 \text{ miles per hour} \]

So, John runs approximately \( 6.55 \) miles per hour.