The five-digit number 45yz0 is divisible by 40. What is the maximum possible value of (y + z)?
Show answer & explanation
Correct answer: C
Explanation
The correct answer is option 3 i.e. 16.
The five-digit number = 45yz0
A number is divisible by 40 if it is divisible by both 5 and 8.
A number is divisible by 5 if its last digit must be 0 or 5.
The given number 45yz0 already ends in 0, so this condition is satisfied.
A number is divisible by 8 if its last three digits must be divisible by 8.
The last two digits = yz0
The number yz0 must be divisible by 8.
If y = z = 8 (maximum value) then yz0 = 880 that is divisible by 8
Maximize y + z = 8 + 8 = 16
Therefore, the maximum possible value of (y + z) is 16.