**1. ODD NUMBERS :**

**Explanation:**

Once in a year: We have only 1 new year every year. (Might sound a little weird -:P) Take odd number out. Here’s only 1 (i.e. once).

Twice in a month : We have 4 weeks every month.

So, 4 weeks = 1st, 2nd, 3rd and 4th. Now take odd numbers out-> 1st & 3rd (i.e. twice).

Four Times in a week : We have 7 days in a week.

Now take odd numbers out 1, 3, 5 and 7 (i.e. four times).

Six Times in a day : We have 12 hours in a day.

Now take odd numbers out 1, 3, 5, 7, 9 and 11 (i.e. six times).

**2. Letter ‘F’ :**

**Explanation:**

Once in a year: 1 year = 12 months, i.e. February ->`F`

comes once while counting in the spelling of all months).

Twice in a month : 1 month has 4 weeks, i.e. First, Fourth -> ‘F’ comes twice in the counting of weeks in a month).

Four Times in a week : 1 week has 7 days i.e. First, Fourth, Fifth -> ‘F’ comes 4 times in the counting of days in a week).

Six Times in a day : 1 day has 24 hours i.e. Four, Five, Fourteen, Fifteen, Twenty-Four -> ‘F’ comes 6 times in the counting of hours in a day).

**3. Letter 'E'**

**Explanation:**

Once in the word ‘yEar’.

Twice "EvEry month".

Four times "EvEry wEEk".

Six times "EvEry wEEkend.