The CAS Registry Mumber 93741-44-7 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 9,3,7,4 and 1 respectively; the second part has 2 digits, 4 and 4 respectively. Calculate Digit Verification of CAS Registry Number 93741-44: (7*9)+(6*3)+(5*7)+(4*4)+(3*1)+(2*4)+(1*4)=147 147 % 10 = 7 So 93741-44-7 is a valid CAS Registry Number.