a batsman makes a score of 100 runs in the 11 th inning and thus increases his average by 5 . find his average after 11 th inning .
"let the average after 11 th inning = x then , average after 10 th inning = x - 5 10 ( x - 5 ) + 100 = 11 x x = 100 - 50 = 50 answer is b"
add(subtract(100, multiply(11, 5)), 5)