A batsman in his 11th inning makes a score of 77 runs, there by increasing his average scores by 3. What is his average score after the 11th inning?

Let the average for scores of 10 innings = a

Sum of the scores of 10 innings = 10a

Score in the 11th inning = 77

$$=$$>  Sum of the scores of 11 innings = 10a + 77

Average increased by 3 after 11th inning

$$=$$>  Average of the scores of 11 innings = a + 3

$$=$$>  Sum of the scores of 11 innings = 11(a+3)

$$=$$>  11(a+3) = 10a + 77

$$=$$>  11a + 33 = 10a + 77

$$=$$>  11a - 10a = 77 - 33

$$=$$>   a = 44

$$\therefore\ $$Average of the scores after 11th inning = a + 3 = 44 + 3 = 47

Hence, the correct answer is Option B