## Elementary and Intermediate Algebra: Concepts & Applications (6th Edition)

A leap year occurs every four years. Each year is equivalent to about $60(60)(24)(365.25)=31,471,200$ seconds, so 4 years is equivalent to around 125,884,800 seconds. Since the number of seconds between leap years is more than 125 million seconds, its scientific notation must involve a positive power of 10.