Prelims 2026 · CSAT / Quantitative Aptitude · Question 60
If x and y are two digits and the number 4x5y790 is divisible by 11, then what is the remainder, if x+y is divided by 11?<br/>
Answer
7
For divisibility by 11, the difference of the sums of alternate digits must be a multiple of 11. For 4x5y790: (4 + 5 + 7 + 0) - (x + y + 9) = 16 - (x + y + 9) = 7 - (x + y). So x + y ≡ 7 (mod 11). Therefore, when x + y is divided by 11, the remainder is 7.