How many days were there in 1997 - 2010?
5,113 days.
1997 was not a leap year, so it had 365 days.
1998 was not a leap year, so it had 365 days.
1999 was not a leap year, so it had 365 days.
2000 was a leap year, so it had 366 days.
2001 was not a leap year, so it had 365 days.
2002 was not a leap year, so it had 365 days.
2003 was not a leap year, so it had 365 days.
2004 was a leap year, so it had 366 days.
2005 was not a leap year, so it had 365 days.
2006 was not a leap year, so it had 365 days.
2007 was not a leap year, so it had 365 days.
2008 was a leap year, so it had 366 days.
2009 was not a leap year, so it had 365 days.
2010 was not a leap year, so it had 365 days.
This gives us 11 non-leap years, or 11 years with 365 days,
which is 11(365), and 3 leap years, or 3 years with 366 days. This
is 3(366). So the number of days in 1997 - 2010 would be
represented by the expression 11(365) + 3(366), which gives us
5,113 days.