what is the remainder when 15^2010 +16^2011 is divided by 7

• Ans is 3
  15^2010/7=1^2010/7
  remainder is 1
  now
  16^2011/7=2^(4*2011)/7=((2^3)^(8044/3))/7=(8^2681)2/7=(1^2681)2/7
  =2/7=remainder 2
  total remainder=1+2/7=3/7=3
• 9 years agoHelpfull: Yes(6) No(1)
• The last digit of 15^2010 is 5 and for 16^2011 is 6.
  Thus, (5+6)/7 = 11/7 i.e remainder=4
• 9 years agoHelpfull: Yes(1) No(4)
• ANS is:4
  15*15 UNIT DIGIT IS 5
  15*15*15 UNIT DIGIT IS 5
  SO 15^2010 UNIT DIGIT IS 5...
  16*16 UNIT DIGIT IS 6
  16*16*16 UNIT DIGIT IS 6
  SO 16^2011 UNIT DIGIT IS 6...
  5+6=11
  11/7=11-7=4 Remainder
  
• 9 years agoHelpfull: Yes(1) No(6)