To round the number 13,415,978 to the nearest five, we look at the last digit (which is 8):
- The nearest multiples of 5 around 13,415,978 are 13,415,975 and 13,415,980.
- Since the last digit (8) is 3 or more (halfway mark), we round up.
Therefore, 13,415,978 rounded to the nearest five is 13,415,980.