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What is the number of zeros at end of number 28! + 29!?
ans-7
Read Solution (Total 5)
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- 28! + 29!
= 28!*(1+29)
= 28! * 30
now 28! has [28/5] + [28/5^2] = 6 zeroes
so 28! * 30 will have 7 zeroes at end. - 8 years agoHelpfull: Yes(34) No(1)
- 28!+29*28!
28!(1+29)
28!*30
28!/5+28!/25*30
5+1+1
7 - 8 years agoHelpfull: Yes(3) No(0)
- At the end zero is only possible if there is any combination of 5 &2 so
28! + 29!
=> 28! + 29 * 28!
=> 30* 28!
=> 30* [ 28* 27 *26 *25...24..*20*.....15 *.12 ..10* ....5*....2 ]
=> by these cobination we will get zero at the end [24*25] + 20+ 15*12 +10+ 5*2
Total no of zero is 7 - 8 years agoHelpfull: Yes(3) No(1)
- 28!+29!=9146650338351415815045120000000. at the end there are only 7 zeros
- 8 years agoHelpfull: Yes(3) No(7)
- answer may b 6
28!/5+5/5+1=6
else correct me - 8 years agoHelpfull: Yes(0) No(8)
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