In 1964, paleontologist discovered the bones of a new species of dinosaur. The age of the dinosaur was estimated using potassium-40dating of rocks surrounding the bones. Alanysis of these rocks indicated that 63.6% of the original amount of potassium-40was still present. The decay model for potassium-40-is A=A0e -0.5292t where t is in billions of years. Let A=0.636 AO in this decay model and estimate the age of the bones of the dinosaur.

The bones are approximately----- billion years old.

(Type an integar or decimal rounded to four decimal places as needed).