The CAS Registry Mumber 1310372-82-7 includes 10 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 7 digits, 1,3,1,0,3,7 and 2 respectively; the second part has 2 digits, 8 and 2 respectively. Calculate Digit Verification of CAS Registry Number 1310372-82: (9*1)+(8*3)+(7*1)+(6*0)+(5*3)+(4*7)+(3*2)+(2*8)+(1*2)=107 107 % 10 = 7 So 1310372-82-7 is a valid CAS Registry Number.