The CAS Registry Mumber 93041-07-7 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 9,3,0,4 and 1 respectively; the second part has 2 digits, 0 and 7 respectively. Calculate Digit Verification of CAS Registry Number 93041-07: (7*9)+(6*3)+(5*0)+(4*4)+(3*1)+(2*0)+(1*7)=107 107 % 10 = 7 So 93041-07-7 is a valid CAS Registry Number.