The CAS Registry Mumber 37478-13-0 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 3,7,4,7 and 8 respectively; the second part has 2 digits, 1 and 3 respectively. Calculate Digit Verification of CAS Registry Number 37478-13: (7*3)+(6*7)+(5*4)+(4*7)+(3*8)+(2*1)+(1*3)=140 140 % 10 = 0 So 37478-13-0 is a valid CAS Registry Number.