Final answer:
Betty should use the equation d = 3 inches × 5.6 miles/inch to calculate the distance from her cabin to the lake, resulting in an actual distance of 16.8 miles.
Step-by-step explanation:
To determine the distance in miles from Betty's cabin to the lake, Betty can use the scale given on the map. Since 1 inch equals 5.6 miles, and the distance between the cabin and the lake measures 3 inches on the map, the equation to calculate the actual distance (d) in miles is:
d = 3 inches × 5.6 miles/inch
Through this calculation, Betty will find that the distance in miles from her cabin to the lake is:
d = 16.8 miles