To find the constant of proportionality, we use the formula:

$k = \frac{\text{Miles Driven}}{\text{Gallons Used}}$

where $k$ represents the constant of proportionality.

Let's calculate $k$ for each pair in the table:

1. For 33 gallons: $k = \frac{930.6}{33} = 28.2$

2. For 43 gallons: $k = \frac{1212.6}{43} = 28.2$

3. For 46 gallons: $k = \frac{1297.2}{46} = 28.2$

Since each calculation results in the same value, the constant of proportionality $k$ is 28.2 miles per gallon.

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Would you like more details or have any questions?

Here are some related questions to deepen your understanding:

1. If Travis uses 50 gallons, how many miles will he drive?
2. How would the constant of proportionality change if Travis’s car efficiency decreased?
3. How can you determine if a relationship is directly proportional from a table of values?
4. If another driver has a different constant of proportionality, what does that indicate?
5. How can you calculate the number of gallons needed for a given number of miles?

Tip: The constant of proportionality remains consistent in a directly proportional relationship, so if one value changes, the other changes at the same rate.