The CAS Registry Mumber 1251002-72-8 includes 10 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 7 digits, 1,2,5,1,0,0 and 2 respectively; the second part has 2 digits, 7 and 2 respectively. Calculate Digit Verification of CAS Registry Number 1251002-72: (9*1)+(8*2)+(7*5)+(6*1)+(5*0)+(4*0)+(3*2)+(2*7)+(1*2)=88 88 % 10 = 8 So 1251002-72-8 is a valid CAS Registry Number.