The CAS Registry Mumber 956484-67-6 includes 9 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 6 digits, 9,5,6,4,8 and 4 respectively; the second part has 2 digits, 6 and 7 respectively. Calculate Digit Verification of CAS Registry Number 956484-67: (8*9)+(7*5)+(6*6)+(5*4)+(4*8)+(3*4)+(2*6)+(1*7)=226 226 % 10 = 6 So 956484-67-6 is a valid CAS Registry Number.