The CAS Registry Mumber 92190-83-5 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 9,2,1,9 and 0 respectively; the second part has 2 digits, 8 and 3 respectively. Calculate Digit Verification of CAS Registry Number 92190-83: (7*9)+(6*2)+(5*1)+(4*9)+(3*0)+(2*8)+(1*3)=135 135 % 10 = 5 So 92190-83-5 is a valid CAS Registry Number.