The CAS Registry Mumber 79388-30-0 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 7,9,3,8 and 8 respectively; the second part has 2 digits, 3 and 0 respectively. Calculate Digit Verification of CAS Registry Number 79388-30: (7*7)+(6*9)+(5*3)+(4*8)+(3*8)+(2*3)+(1*0)=180 180 % 10 = 0 So 79388-30-0 is a valid CAS Registry Number.