The CAS Registry Mumber 94235-50-4 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 9,4,2,3 and 5 respectively; the second part has 2 digits, 5 and 0 respectively. Calculate Digit Verification of CAS Registry Number 94235-50: (7*9)+(6*4)+(5*2)+(4*3)+(3*5)+(2*5)+(1*0)=134 134 % 10 = 4 So 94235-50-4 is a valid CAS Registry Number.