Question

Which of the following is not a constant number?

• A. number of days in a week
• B. number of seconds in a minute
• C. number of inches in a foot
• D. number of days in a year

Answer 1

The correct option is D number of days in a year

Constant numbers are fixed numbers that do not change over time.
We know that there are 7 days in a week, 60 seconds in a minute and 12 inches in a foot and that means that these numbers are fixed.
We also know that there are 366 days in a leap year and 365 days in a non-leap year which means number of days in a year changes over time.