#6.find the number of zeroes in 1^1*2^2*3^3...48^48*49^49?

• since only the product of 5*2 results a 0
  so we have to count no of 5's as well as no of 2's.
  we also know the no of 5's will be less than the no of 2's
  so we will count only the 5's...
  thus 5^5*10^10*15^15*20^20*25^25*30^30*35^35*40^40*45^45 gives
  (5+10+15+20+25+25+30+35+40+45)=250 5's
  thus total no of 0's will be 250.
  
• 11 years agoHelpfull: Yes(49) No(1)
• just count the no of 5 in qus bcoz no. of 5 is less than no.of 2 and every 5*2=10
  so 5^5,(5*2)^10,(5*3)^15,20^20,25^25,30^30,35^35,40^40,45^45=225
• 11 years agoHelpfull: Yes(5) No(11)
• ans 250 ...the guyz who got 225 did a mistake at 25^25
• 11 years agoHelpfull: Yes(5) No(1)
• 250 zeroes is the right ans....we just have to calulate the number of 5 in the above expression...
• 11 years agoHelpfull: Yes(2) No(2)
• TOTAL 100 ZERO'S due to the zeros are come from 10^10,20^20,30^30,40^40
  so we get 10,20,30,40 zreo resp.
  the total zero will be 100 zero.
  
• 11 years agoHelpfull: Yes(1) No(7)
• 5^5,10^10,15^15,20^20,25^25,30^30,35^35,40^40,45^45 ..
  5+10+15+20+25+30+35+40+45=225 zeros will be there
• 11 years agoHelpfull: Yes(1) No(6)
• 5*5, 10*10, 15*15, 20*20, 25*25, 30*30, 35*35, 40*40, 45*45
  
  5+10+15+20+25+30+40+45
  225 zeros will be
  
• 11 years agoHelpfull: Yes(0) No(1)
• ans 250
  total number of 5's present
  5+10+15+20+(25+25)+30+35+40+45=250
• 9 years agoHelpfull: Yes(0) No(0)