Question

January 1, 2008 is Tuesday, what day of the week lies on January 1, 2009.

• A. Monday
• B. Wednesday
• C. Thursday
• D. Saturday

Answer 1

Answer:

C. Thursday

Calculation Method

A standard calendar year has 365 days, but leap years have 366 days. To find the day of the week for the next year, you calculate the number of "odd days" (the remainder when dividing the total days by 7).

• Identify the Year Type: The year 2008 is completely divisible by 4, making it a leap year.

• Count the Days: Because 2008 is a leap year, it contains 366 days instead of 365. This includes the extra day on February 29, 2008.

• Calculate Odd Days: Divide 366 by 7 to find the remainder.
  $\text{366 days} \div 7 = \text{52 weeks and 2 days remainder}$

• Shift the Calendar: A leap year always advances the calendar by 2 odd days.

Final Step

• Start day: Tuesday

• Tuesday + 2 days = Thursday