Latest TCS Aptitude Question SOLUTION: find the number of zeroes in 1^1*2^2*3^3...48^48*49^49

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(#M40012410) TCS Numerical Ability question Keep an EYE

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

Asked In TCS K.Veena (11 years ago)

Unsolved Read Solution (11)

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nitin dutta  (11 years ago)

sorry i have done calculation wrong...
250...
5^5+10^10+15^15....45^45 will have zeroes
total=5+10+15+20+50+30+35+40+45
250

Is this solution Helpfull? Yes (23) | No (8)  

Akshay Bansal  (11 years ago)

10+20+30+40 =100 zeros
eg
10^10= 10 zeros
20^20=20 zeros

Is this solution Helpfull? Yes (6) | No (2)  

lucky  (11 years ago)

ya it is 250

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manish  (11 years ago)

pallavi ji: ANS/: 5+10+15+20+50+30+35+40+45=250 ///(5^5+10^10+++45^45)
WHEN U multiply 1^1***5^5 will get d 5 zero bcz 1*2*3*4*5=120 has 1 zero in d last so 5*1=5 nd similarly 6***10 has 10*1= 10 so up to no 20).bt 21*22**25 hs 2 zero in last so just double that of actual value i.e 25*2=50. nd so on. last 4 no 46,47,48,49 multiplication can't give any zero so neglect these nos. ys u need calculator to check sm time tcs allowe cator, hope u got it ....pallavi

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Mridul Trivedi  (11 years ago)

But nitin here the series is multipled not added!!!

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Pallavi Barjatiya  (11 years ago)

m agree with paridhi. . hay you all sayin ans 250.
please xplain how ?? unable to undrstand the logic.

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manish  (11 years ago)

2 ND Approach-
count total no of pow of 5 nd sum is d answer.i.e 5^5+(10=5*2)^10+(15=5*3)^15+...+(25=5*5)^25 means 5^50+....+(45=9*5)45= 5+10+15+20+50+30+35+40+45=250

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nitin dutta  (11 years ago)

250...
5^5+10^10+15^15....45^45 will have zeroes
total=5+10+15+20+50+30+35+40+45
200

Is this solution Helpfull? Yes (3) | No (3)  

Mridul Trivedi  (11 years ago)

13 zeros should be the answer
because after squaring number having 5 at end oy 10 will give 0.
number with 5 at end will be (5*5)=25, (15*15), (25*25),(35*35,(45*45)
number with 0 at last will give 2 zero!!ie 10,20,30,40

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ryan  (11 years ago)

5+10+15+20+50+30+35+40+45= 250
ans is 250

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Paridhi Saxena  (11 years ago)

how can u add 5^5? It wont contribute any 0.. 5x5x5x5.. always give unit digit 5, never 0.. same case with 15, 25, 35, and 45.
so I guess, answer will be 100.. (10+20+30+40)

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