The CAS Registry Mumber 107244-78-0 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, 7 and 8 respectively. Calculate Digit Verification of CAS Registry Number 107244-78: (8*1)+(7*0)+(6*7)+(5*2)+(4*4)+(3*4)+(2*7)+(1*8)=110 110 % 10 = 0 So 107244-78-0 is a valid CAS Registry Number.