Problem
NT-B1-M10-P006 Digit Sum and Remainder
#6
★★☆☆☆ Level 2 of 5
Find all digits \(x\) for which \(52x47\) is divisible by \(9\).
The digit sum must be divisible by \(9\).
The digit sum is \(5+2+x+4+7=18+x\). This is divisible by \(9\) exactly for \(x=0\) or \(x=9\).
Good task for enforcing the condition that \(x\) is a digit.