The scale of the map will be: 1 inch = 50 miles
Explanation
Actual area of the Mojave desert is 25,000 square miles and the scale drawing has an area of 10 square inches.
Suppose, the scale of the map is: 1 inch =
miles.
So, 1 square inches =
square miles
and 10 square inches =
square miles
So, the equation will be .....

Thus, the scale of the map will be: 1 inch = 50 miles.