The CAS Registry Mumber 47500-83-4 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 4,7,5,0 and 0 respectively; the second part has 2 digits, 8 and 3 respectively. Calculate Digit Verification of CAS Registry Number 47500-83: (7*4)+(6*7)+(5*5)+(4*0)+(3*0)+(2*8)+(1*3)=114 114 % 10 = 4 So 47500-83-4 is a valid CAS Registry Number.