The CAS Registry Mumber 107244-84-8 includes 9 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 6 digits, 1,0,7,2,4 and 4 respectively; the second part has 2 digits, 8 and 4 respectively. Calculate Digit Verification of CAS Registry Number 107244-84: (8*1)+(7*0)+(6*7)+(5*2)+(4*4)+(3*4)+(2*8)+(1*4)=108 108 % 10 = 8 So 107244-84-8 is a valid CAS Registry Number.