what is the smallest no . which must be added to 53403977 so as to obtain a sum which is divisible by 11 ?
"for divisibility by 11 , the difference of sums of digits at even and odd places must be either zero or divisible by 11 . for 53403977 , difference = ( 5 + 4 + 3 + 7 ) - ( 3 + 0 + 9 + 7 ) = 19 - 19 = 0 . = > 53403977 is also divisible by 11 c"
divide(multiply(53403977, 11), 53403977)