15 Aug, 1947 = (1946 years + Period from 1.1.1947 to 15.8.1947)

Odd days in 1600 years = 0 

Odd days in 300 years = 1

46 years = (35 ordinary years + 11 leap years) = (35 x 1 + 11 x 2)= 57 (8 weeks + 1 day) = 1 odd day 

Jan.   Feb.   Mar.   Apr.   May.   Jun.   Jul.   Aug 

( 31 + 28 + 31 + 30 + 31 + 30 + 31 + 15 ) = 227 days = (32 weeks + 3 days) = 3 odd days.

Total number of odd days = (0 + 1 + 1 + 3) = 5 odd days. 

Hence, as the number of odd days = 5 , given day is Friday.

Looking into the alphabets there are six such pairs namely ON, HONE, ST, TRAPHO, TRAPHON, RAP.

1. ON  - NO

2. HONE - EFGH

3. ST - ST

4. TRAPHO - OPQRST

5. TRAPHON - NOPQRST

6. RAP - PQR

Total number of votes = 7500 

Given that 20% of Percentage votes were invalid

 => Valid votes = 80%

 Total valid votes = 7500*(80/100) 

1st candidate got 55% of the total valid votes. 

Hence the 2nd candidate should have got 45% of the total valid votes 

=> Valid votes that 2nd candidate got = total valid votes x (45/100) 

7500*(80/100)*(45/100) = 2700

Letters in the word           Letters in the alphabet

$$\begin{gathered} CHA \\ - - \end{gathered}$$                            $$\begin{gathered} CBA \\ - - \end{gathered}$$

$$\begin{gathered} RS \\ -- \end{gathered}$$                             $$\begin{gathered} RS \\ -- \end{gathered}$$