A person was born on 21 September 2018. What day of the week will be on his 11th birthday?
Show answer & explanation
Correct answer: C
Explanation
First, the day of September 21, 2018:
September 21, 2018 = Friday
From 2018 to 2029 (11 years later)
Each ordinary year = +1 day
Each leap year = +2 days
Leap years in between: 2020, 2024, 2028
8 ordinary years → +8 days
3 leap years → +6 days
Total change:
8 + 6 = 14 days
14 / 7 = 0
Conclusion:
There will be no change in the day.
Therefore, September 21, 2029, will also be a Friday.
Correct Answer: C) Friday