Quant by Arun Sharma

You've got both the answers right. The first equation indeed gives a remainder of 22. Arun Sharma has a lot of incorrect answers, so better is to check it using a calculator.

Similarly, there's no way the 2nd question can have any other remainder apart from 1. So rest assured on that. If your methodology is right, your answers would be right too. Don't trust Arun Sharma's answers too much.



Can someone provide the link to the number sysrtm questions that were discussed were discussed on this thread so that i can put new question overe here in which i am having the problems and checking the one that have already been solved.

There are 205 pages on this thread and it is not possible for me to find the question related to number sutem:biggrin:
Can someone provide the link to the number sysrtm questions that were discussed were discussed on this thread so that i can put new question overe here in which i am having the problems and checking the one that have already been solved.

There are 205 pages on this thread and it is not possible for me to find the question related to number sutem:biggrin:

There are two threads completely dedicated to Number Systems:

http://www.pagalguy.com/discussions/number-system-25000852 (This one has been closed now)

http://www.pagalguy.com/discussions/number-system-questions-discussions-25043728

Can someone help me in this questions:

Find the remainder when 21^875 is divisble by 17

a)8 b)13 c)16 d)9And please specify the concept as well


*********************************************
Find the remainder when 75^80 is divided by 7

a)4 b)3 c)2 d)6

Please someone can give how to solve these question's






Another Question:



Find the remainder when (2222^5555 +5555^2222)/7


My answer is coming ou to be 9 but in the book the answer is zero ?Can some help

Can someone help me in this questions:

Find the remainder when 21^875 is divisble by 17

a)8 b)13 c)16 d)9And please specify the concept as well

The answer should be 13. Here's how to proceed using the "mod" method:

21 = 4 mod 17 (i.e. 21/17 gives a remainder of 4)
21^2 = 4^2 mod 17 = 16 mod 17 = (-1) mod 17
(21^2)^437 = 21^874 = (-1)^437 mod 17 = (-1) mod 17

Now, 21^875 = 21^874 * 21 = (-1) * 4 mod 17 = -4 mod 17 = 13 mod 17 (17-4 = 13)

Hope you understood the method. It seems a bit long but once you understand the method, it's very easy to follow.
Can someone help me in this questions:

Find the remainder when 21^875 is divisble by 17

a)8 b)13 c)16 d)9And please specify the concept as well


ans is 13....

divide 21/ 17 ...rem is 4...now 4^875....

or 16^437 * 4

16/17 = -1

-1^437 *4 =-4

and 17-4= 13 ans


Another Question:

Find the remainder when (2222^5555 +5555^2222)/7

My answer is coming ou to be 9 but in the book the answer is zero ?Can some help


remainder 2222/7 = 3

3^5555 = 27^1851 * 9

27/7 = -1

-1^ 1851 * 9= -9

-9/7 = -2

remainder 5555/7 = 4

4 ^ 2222 = 64^740 * 16

64/7 = 1

1^740 * 16=16

16/7 = 2


so -2+2=0 ans

or 16^437 * 4

16/17 = -1

-1^437 *4 =-4

and 17-4= 13 ans


Can you please explain me the above steps as why it was done like this only.

Please elaborate your point as well as why you split in 16^437 * 4 way only and
16/17 = -1 dividing first and then doing -1^437 *4 =-4 .


It will be very kind of you if you can provide the method as well in solving these type of questions

or 16^437 * 4

16/17 = -1

-1^437 *4 =-4

and 17-4= 13 ans


Can you please explain me the above steps as why it was done like this only.

Please elaborate your point as well as why you split in 16^437 * 4 way only and
16/17 = -1 dividing first and then doing -1^437 *4 =-4 .


It will be very kind of you if you can provide the method as well in solving these type of questions


take the dividend closer to the divisor so that it may result in rem of +1 or -1, it helps in quick calculations as -1 or +1 raise to ny power can be calculated by just lookin at its power........
You've got both the answers right. The first equation indeed gives a remainder of 22. Arun Sharma has a lot of incorrect answers, so better is to check it using a calculator.

Similarly, there's no way the 2nd question can have any other remainder apart from 1. So rest assured on that. If your methodology is right, your answers would be right too. Don't trust Arun Sharma's answers too much.



Ca you please re-confirm the answers to these 2 questions as well
hitesh1907 Says
Ca you please re-confirm the answers to these 2 questions as well

As I said, you can check the 1st question by a calculator. And about the 2nd question, it has to be 1. This is because 43 = 1 mod 7, so 43 raised to any power would result in a remainder of 1.

hi!
i've just started out with my cat 2010 preparation. need to give 1 decent try before completely abandoning this idea.
need some help here,
a number 20 is divided into 4 parts that are in an AP such that the product of the first and fourth to the product of the 2nd and 3rd is 2:3. find d largest part.
:lookround:

hi!
i've just started out with my cat 2010 preparation. need to give 1 decent try before completely abandoning this idea.
need some help here,
a number 20 is divided into 4 parts that are in an AP such that the product of the first and fourth to the product of the 2nd and 3rd is 2:3. find d largest part.
:lookround:

let the nos. be :
a-3d, a-d,a + d, a + 3d
thn
a = 5
also
(a^2 - 9d^2) / (a^2-d^2) = 2/3
75 - 27d^2 = 50 - 2d^2
25 = 25d^2
1 = d^2
d = 1
largest part = 8

how did u get 'a' as 5 ? and a-2d, a-d, a, a+d, a+2d would be in ap. that would make it 5 nos. here we have just 4nos in ap.
and d answer given in d book is 8.

how did u get 'a' as 5 ?
and d answer given in d book is 8.

add all the nos.
u get 4a = 20
a = 5

a-2d, a-d, a, a+d, a+2d would be in ap. that would make it 5 nos. here we have just 4nos in ap.

p2w Says
a-2d, a-d, a, a+d, a+2d would be in ap. that would make it 5 nos. here we have just 4nos in ap.

hey srry dude i really m doin these silly err a lot these days, just coping up with the cat fiasco, anyways i have edit my earlier post, please chk it...
what is the last 2 digits of
a)(101*102*103*197*198*199)
b)(65*29*37*63*71*87)
plz do post the full method..!!!!!

1--04
2--45
is that correct..?
remainder when 7^99/2400
a.1 b.343 c.49 d.7

yes i got too...343..
1--04
2--45
is that correct..?


first one i think the ans is 64
Says
first one i think the ans is 64

Ya it would be 64.