[amitshanky]

1)LCM of first 100 natural numbers is K, then LCM of first 105 natural numbers will be

k,101k,10403k,100k

[shanks4mba]

Originally Posted by amitshanky

1)LCM of first 100 natural numbers is K, then LCM of first 105 natural numbers will be

k,101k,10403k,100k

LCM(1, 100) = all the 25 primes..
so from 101 to 105 we have 101,103 as prime
hence it shud be 101*103k = 10403k

[Ankurb]

Originally Posted by amitshanky

1)LCM of first 100 natural numbers is K, then LCM of first 105 natural numbers will be

k,101k,10403k,100k

LCM(first 100 numbers) = product of highest powers of all prime numbers = k
LCM(first 105 numbers) = 101 *103 *k = 10403k

[madnikhil]

Originally Posted by amitshanky

1)LCM of first 100 natural numbers is K, then LCM of first 105 natural numbers will be

k,101k,10403k,100k

EAsy one
101 and 103 are prime no.
so,
10403k will be answer..

[.mba]

AB is a two digit number in base n such that (AB)to base n = 5(BA)to base n.

Which of the following is a possible vale of

n?

(1) 12
(2) 14
(3) 16

(4) 21

[manojmsr]

since for 100numbers the lcm is k for 105 it ll be k*101*103 as they are the oly prime nos in btw 100 to 105....

So i guess the answer is 10403k i guess..

[divishth]

Originally Posted by .mba

AB is a two digit number in base n such that (AB)to base n = 5(BA)to base n.

Which of the following is a possible vale of

n?

(1) 12
(2) 14
(3) 16

(4) 21

Answer is 21

[Abhinav90]

Originally Posted by divishth

Answer is 21

Plz post approach...I m uneasy with bases...

[shanks4mba]

Originally Posted by .mba

AB is a two digit number in base n such that (AB)to base n = 5(BA)to base n.

Which of the following is a possible vale of

n?


(1) 12
(2) 14
(3) 16

(4) 21

given (AB)n = 5(BA)n
An + B = 5Bn + 5A
A(n-5) = (5n - 1)B
A/B = 5n-1/n-5
now for n = 12 we get A/B = 59/7...which not possible as A shub be from 0 to 11
now for n = 14 we get A/B = 69/9 = 23/3 not possible
now for n = 16 we get A/B = 79/11..not possible
now for n = 21 we get A/B = 104/16 = 13/2...which can be possible in the base system of 21..hence ans is 21

[Abhinav90]

Originally Posted by shanks4mba

given (AB)n = 5(BA)n
An + B = 5Bn + 5A
A(n-5) = (5n - 1)B
A/B = 5n-1/n-5
now for n = 12 we get A/B = 59/7...which not possible as A shub be from 0 to 11
now for n = 14 we get A/B = 69/9 = 23/3 not possible
now for n = 16 we get A/B = 79/11..not possible
now for n = 21 we get A/B = 104/16 = 13/2...which can be possible in the base system of 21..hence ans is 21

how to check?
Why did you accepted 13/2=6.5 and not 23/3 = 7.666 ?
plz edify !