A 9-digit number 846523X7Y is divisible by 9, and Y - X = 6.
Find the value of
Show answer & explanation
Correct answer: C
Explanation
The correct answer is option 3 i.e. 6.
We know,
Divisibility rule of 9: a number is divisible by 9 if the sum of its digits is also divisible by 9.
According to the question;
⇒ 8 + 4 + 6 + 5 + 2 + 3 + 7 + X + Y = 45 (Multiple of 9)
⇒ X + Y + 35 = 45
⇒ X + Y = 10 ---- (1)
We have,
⇒ Y - X = 6 ---- (2)
Solving equation (1) and (2), we get
⇒ X = 2 and Y = 8
⇒ √(2X + 4Y) = √(4 + 32) = √36
⇒ 6