(((13!)^16)-((13!)^8))/(((13!)^8)+((13!)^4))=a
then what is the units digit for a/((13!)^4)=

• 9
  
  (((13!)^16)-((13!)^8))/(((13!)^8)+((13!)^4))=a
  
  solving it , we get
  a/((13!)^4)= ((13!)^4-1)
  last digit of (13!)^4 will be 0.
  
  so last digit of ((13!)^4-1) will be 9.
• 12 years agoHelpfull: Yes(1) No(0)
• 9
  (13!)^8.((13!)^8-1)/(13!)^4((13)^4+1) = a
  
  solving we get
  a/(13!)^4=(13!)^4-1
  last digit (13!)^4 is 0
  Answer=9
• 12 years agoHelpfull: Yes(1) No(1)