Question

Claire is hiking up the South Kaibab Trail at the Grand Canyon. The table shows Claire’s altitude above sea level every 15 minutes after she starts to hike. Use a graph and an equation to find how long it will take Claire to reach the rim of the canyon at 7260 feet.

Answer 1

The table shows a linear relation. The slope is (3240-2940)/(30-15) = 300/15 = 20.
The equation is f(x) = 20x + 2640.
To reach 7260 feet: 
7260 = 20x + 2640
20x = 4620
x=231 minutes