Q. The sum of 25 consequtive integers (including negative, positive and zero) is divisible by

Option
a) 5
b) 10
c) 25
d) 15

• Both 5 and 25.
  
  If numbers are
  a-12,a-11,...,a, a+1,a+2,...,a+12
  Then sum of integers = 25a which is divisible by 5 and 25.
• 11 years agoHelpfull: Yes(21) No(3)
• suppose 25 consequtive no. are a,a+1,a+2...a+24
  sum of them is-> a+(a+1)+(a+2)...+(a+24)
  25a+(1+2+3+....+24)
  25a+[24/2(1+24)]
  25a+300
  25(a+12)...which is divisible by 25.
• 11 years agoHelpfull: Yes(8) No(6)
• maximum negative no. =-12
  max positive no. =12
  then in between these series only series may be-12,-11,.....0.....11,12
  and sum =0
  if it starts from -11 to 13 then sum will be 25
  if it starts from -10+(-9)+......+0+.......+9+10+11+12+13+14=50
  if -9 to 15=10+11+12+13+14+15=75........thats why it will be divisible by 25
  
• 11 years agoHelpfull: Yes(3) No(2)