Quant by Arun Sharma

MBA CAT 2024
2338
Hi,
I have a question from number system
Find the remainder when 123456789101112.......484950 is divided by 16.
a.3 b.4 c.5 d.6
Plz explain how to approach this one


Test of divisibility by 16 is to check whether the last 4 digits are divisible by 16 or not.

In this case:

4950 mod 16

Remainder is 6.

Option (D)
2339

Need help in solving Geometry LOD II questions.
Page - 340
LOD II, Question no - 22


PP' & QQ' are two direct common tangents to two circles intersecting at points A & B. The common chord on produced intersects PP' in R & QQ' in S. Which of the following is true ??

a. (RA^2) + (BS^2) = AB^2
b. RS^2 = (PP'^2) + (AB^2)
c. RS^2 = (PP'^2) + (QQ'^2)
d. RS^2 = (BS^2) + (PP'^2)
e. None of these

2340

Hi Puys ,

I want to understand the solution of Problem number 38 , 39 LOD 3 of chapter 2 Averages .....

Thx in advance

2341
Hi Puys ,

I want to understand the solution of Problem number 38 , 39 LOD 3 of chapter 2 Averages .....

Thx in advance

Post the questions here.
2342

Please help me solve this!
what is remainder when 2(8!)-21(6!) divides 14(7!)+14(13!)?
a.1 b.7! c.8! d.9!
ans=7!

2343
Please help me solve this!
what is remainder when 2(8!)-21(6!) divides 14(7!)+14(13!)?
a.1 b.7! c.8! d.9!
ans=7!


Denominator is 16*7!-3*7!=13*7!

Numerator is 14*7!+14!

On division

(14*7!/13*7!)+(14!/13*7!)

First part the remainder is 7! as the remainder of 14/13 is 1 and it has to be multiplied with the common factor crossed out which was 7!

Second part is completely divisible.So, final remainder is 7!

Option (B)
2344

hi puys i wanted to know whether arun sharma book is good to brush up ur basics initially for cat....or if not please suggest some sources to strengthen basics plzzzzzzzzzz help.. thankyou to alll

2345
prats92 Says
hi puys i wanted to know whether arun sharma book is good to brush up ur basics initially for cat....or if not please suggest some sources to strengthen basics plzzzzzzzzzz help.. thankyou to alll

Arun Sharma is really good to brush up your basics. Although the answers provided to some of the questions are wrong but the concepts are explained very well, so you can start with it. If you get stuck with some questions of Arun Sharma, you can always post them here and people would help you out.
2346

1.A purse contains, in all, 378 coins consisting of one rupee,50 paise and 25 paise. The
total values of these coins are in the ratio of 13:11:7. How many coins of one rupee does
the purse contain?

2.Last year ,the prices of tea and coffee were in the ratio of 2:3 . Between last year and
this year, the price of tea has risen in the ratio of 5:6 and that of coffee, in the ratio of 7:8.
If this year, a kg of coffee and a kg of tea together cost Rs 51,how much does a kg of
coffee cost?

2347
A purse contains, in all, 378 coins consisting of one rupee,50 paise and 25 paise. The
total values of these coins are in the ratio of 13:11:7. How many coins of one rupee does
the purse contain?


Let the coins of 1 Re be x that of 50 p be y and that of 25 p be z

x+y+z=378

x:y/2:z/4=13:11:7

2x/y=13/11 => y=22x/13

2y/z=11/7 => z=14y/11= 28x/13

Substitute in first equation:

x+22x/13+28x/13=378

63x=378*13

x=78
y=132
z=168

So, there are 78 1 Re coins.
2348

Amitabh has a certain no. of toffees such that if he distributes them among ten children he has nine left,if he distributes amongst 9 children he would have 8 left ...and so on until if he distributes amongst 5 children he should have 4 left . what is second highest no of toffees he could have with him?
a.2519b.7559c.8249d.none of these
ans=d
how to approach this?

2349
Amitabh has a certain no. of toffees such that if he distributes them among ten children he has nine left,if he distributes amongst 9 children he would have 8 left ...and so on until if he distributes amongst 5 children he should have 4 left . what is second highest no of toffees he could have with him?
a.2519b.7559c.8249d.none of these
ans=d
how to approach this?

For such problems, you just need to find the LCM of 10, 9, 8, 7, 6 and 5, which comes out to be 2520. Since the number of toffees left are one less than the number of children, the least number of toffees could be 2519 (2520 - 1). The next number would be 2519 + 2520, then 2519 + 2520*2 and so on. Thus, 2519 + 2520*x, where x is a non-negative integer.

So, the number could be 2519, 5039, 7559 and so on. In such a case, finding the highest or second highest number of toffees is impossible, as it could theoretically be any number. Thus, the answer should be (d), although I think the answer should be 'Cannot be determined'.
2350

Hi Puys,

If x-4 + y-4=4, then how many integer values can be set(x,y) have?

a) infinite
b)5
c)16
d)9
e)25

2351
Hi Puys,

If x-4 + y-4=4, then how many integer values can be set(x,y) have?

a) infinite
b)5
c)16
d)9
e)25

Is the answer 9?? I'm not very sure about the answer.
2352

answer is 16
but can u plz xplain the concept
i am able to find 5 such combination
0,4
1,3
2,2
3,1
4,0

2353
answer is 16
but can u plz xplain the concept
i am able to find 5 such combination
0,4
1,3
2,2
3,1
4,0

I'm getting these combinations:

x = 0, y = 4
x = 1, y = 3, 5
x = 2, y = 2, 6
x = 3, y = 1, 7
x = 4, y = 0, 8

We can't take any negative values for x as then x-4 would become more than 4, thus the overall answer can't be 4. Arun Sharma has quite a few misprints, but it's better if someone else confirms.

PS: Please quote the post you're replying to.

Edit: We can actually get more combinations, didn't think of them earlier:

x = 5, y = 1, 7
x = 6, y = 2, 6
x = 7, y = 3, 5
x = 8, y = 0

This way we do get 16 as the total number of combinations. Should be right this time.
2354
Hi Puys,

If x-4 + y-4=4, then how many integer values can be set(x,y) have?

a) infinite
b)5
c)16
d)9
e)25


As both are non-negative we have the following combinations

4+0=>(8,4); (0,4)
0+4=>(4,; (4,0)
1+3=>(5,7); (3,7); (5,1); (3,1)
3+1=>(1,3); (1,5); (7,3); (7,5)
2+2=>(6,2); (6,6); (2,6); (2,2)

So, my take would be 16
2355

Is there a similar thread for DI by Arun Sharma..?Sorry for spamming.
Is it a good book to start your DI prep.?

2356
Is there a similar thread for DI by Arun Sharma..?Sorry for spamming.
Is it a good book to start your DI prep.?

There is a general thread for LR/DI, where you can post your doubts from Arun Sharma:

http://www.pagalguy.com/discussions/cat-2010-lr-di-thread-25048796
2357

If you form a subset of integers chosen from between 1-3000 such that no 2 integers add up to a multiple of nine what can be maximum no of elements in subset?
a.1668b.1332c.1331d.1334
ans=c

how to solve this?