The last day of a century cannot be: |
Tuesday Thursday Saturday All of the above |
All of the above |
100 years contain 5 odd days. So, last day of 1st century is 'Friday' 200 years contain (5×2)=10 odd days =3 odd days. So, last day of 2nd century is 'Wednesday'. 300 years contain (5×3)=15 odd days =1 odd day. So, last day of 3rd century is 'Monday'. 400 years contain 6 odd days. So, last day of 4th century is 'Saturday' Since the order is continually kept in successive cycles, we see that the last day of a century cannot be Tuesday, Thursday or Saturday. |