Official Quant thread for CAT 2013

@Estallar12 said:
So much spamming on Quant Thread ? Move to SB. Question:A not-so-good clockmaker has four clocks on display in the window. Clock #1 loses 15 minutes every hour. Clock #2 gains 15 minutes every hour relative to Clock #1 (i.e., as Clock #1 moves from 12:00 to 1:00, Clock #2 moves from 12:00 to 1:15).Clock #3 loses 20 minutes every hour relative to Clock #2. Finally, Clock #4 gains 20 minutes every hour relative to Clock #3. If the clockmaker resets all four clocks to the correct time at 12 noon, what time will Clock #4 display after 6 actual hours (when it is actually 6:00 pm that same day) ?P.S. Spam Posts delete kar dena!
5 pm
@Logrhythm said:
What a slow start to the sunday...post karo yaar questions.. Q: Amit has 2n marbles numbered 1 through 2n. He removes n marbles that are numbered consecutively. The sum of the numbers on the remaining marbles is 1615. Find all possible values of n.
(n)(2n+1)-n/2(m+1+m+n)=1615
n(2n+1-m-n/2-1/2)=1615
n(3n/2-m-1/2)=1615
n(3n-2m-1)=3230
3230=17*19*5*2
1615*2=x(x+1)
x(x+1)=3230
x is close to 59
atleast n has to be 59
values 85 95 170 190 323 646 1615 3230 ?

Q1:


amit threw five standard dice simultaneously. He found that the product of the numbers on the top faces was 216. which of the following couldn't be the sum of numbers on top five faces:
a: 17
b: 19
c: 18
d: 20


Q2:

The number 2006! is written in base 22. How many zeroes are there at the end?
a: 500
b: 450
c: 200
d: 199


Q3:

X & Y are two natural no's such that X+Y=949. LCM of X & Y is 2628. What is the HCF of X & Y??
a: 23
b: 73
c: 69
d: none

Answer along with approach is must
@DeAdLy said:
Q1:amit threw five standard dice simultaneously. He found that the product of the numbers on the top faces was 216. which of the following couldn't be the sum of numbers on top five faces:a: 17b: 19c: 18d: 20Q2:The number 2006! is written in base 22. How many zeroes are there at the end?a: 500b: 450c: 200d: 199Q3:X & Y are two natural no's such that X+Y=949. LCM of X & Y is 2628. What is the HCF of X & Y??a: 23b: 73c: 69d: noneAnswer along with approach is must
1)
216=2^3*3^3
20=9+4+3+2+1+1
17=3+3+3+2+2+2
19=6+6+2+3+1+1

18 not possible


2)22=11*2
no of 11's in 2006=182+16+1=199

3)X+Y=949
h(a+b)=949
h(a*b)=2628

h(a*b-a-b)=1679=23*73

if h=23
a+b is not an integer

hence h=73
@Logrhythm said:
What a slow start to the sunday...post karo yaar questions.. Q: Amit has 2n marbles numbered 1 through 2n. He removes n marbles that are numbered consecutively. The sum of the numbers on the remaining marbles is 1615. Find all possible values of n.
2n*(2n + 1)/2 - {[n*(n + 1)/2] + nx} = 1615

=> 3n^2 + n - 2nx = 3230

=> when n = 34 , x = 4
=> when n = 38 , x = 15

it means , (sum of 1 to 68) - (sum of 5 to 38) = 1615
(sum of 1 to 76) - (sum of 16 to 53) = 1615

possible values of n = 34 and 38
@Subhashdec2 said:
(n)(2n+1)-n/2(m+1+m+n)=1615n(2n+1-m-n/2-1/2)=1615n(3n/2-m-1/2)=1615n(3n-2m-1)=32303230=17*19*5*21615*2=x(x+1)x(x+1)=3230x is close to 59atleast n has to be 59values 85 95 170 190 323 646 1615 3230 ?
@jain4444 said:
2n*(2n + 1)/2 - {[n*(n + 1)/2] + nx} = 1615 => 3n^2 + n - 2nx = 3230 => when n = 34 , x = 4 => when n = 38 , x = 15 it means , (sum of 1 to 68) - (sum of 5 to 38) = 1615 (sum of 1 to 76) - (sum of 16 to 53) = 1615 sum of all the possible values of n = 34 + 38 = 72
answer: 34 and 38...
@DeAdLy said:
Q1:amit threw five standard dice simultaneously. He found that the product of the numbers on the top faces was 216. which of the following couldn't be the sum of numbers on top five faces:a: 17b: 19c: 18d: 20
c18
@DeAdLy said:
Q2:The number 2006! is written in base 22. How many zeroes are there at the end?a: 500b: 450c: 200d: 199

D199
[2006/11] +[182/11] + [16/11]
@DeAdLy said:
Q3:X & Y are two natural no's such that X+Y=949. LCM of X & Y is 2628. What is the HCF of X & Y??a: 23b: 73c: 69d: none

B73

nos are 73*9 and 73*4
@DeAdLy said:
Answer along with approach is must
@iLoveTorres overall aptitude

@Subhashdec2 said:
1)216=2^3*3^320=9+4+3+2+1+117=3+3+3+2+2+219=6+6+2+3+1+118 not possible2)22=11*2no of 11's in 2006=182+16+1=1993)X+Y=949h(a+b)=949h(a*b)=2628h(a*b-a-b)=1679=23*73if h=23a+b is not an integerhence h=73
18 possible hai sir... (2,3,1,6,6)
@DeAdLy said:
Q1:amit threw five standard dice simultaneously. He found that the product of the numbers on the top faces was 216. which of the following couldn't be the sum of numbers on top five faces:a: 17b: 19c: 18d: 20Q2:The number 2006! is written in base 22. How many zeroes are there at the end?a: 500b: 450c: 200d: 199Q3:X & Y are two natural no's such that X+Y=949. LCM of X & Y is 2628. What is the HCF of X & Y??a: 23b: 73c: 69d: noneAnswer along with approach is must
1) 216 = 2^3*3^3
18 -> 6+6+3+2+1 or 8+3+3+3+1 (possible)
20 -> 6+6+6+1+1 (possible)
17 -> 6+4+3+3+1 (possible)

hence 19 not possible @Subhashdec2 @joyjitpal i guess u guys took 6 dices plus the product of ur numbers is also not coming out to be 216 (at places)...pls check...

2) 2006/11 = 182/11 = 16/11 = 1

hence, 199 0's

3) X = ap and Y = bp (a and b are coprime)
p(a+b) = 949 = 13*73
abp = 2628 = 2^2*3^2*73

hence p = 73...



@DeAdLy
1 question : 17 is not possible.
2nd question : 199
3rd question : 73
@perseverance07 said:
@DeAdLy1 question : 17 is not possible.2nd question : 1993rd question : 73
consider the case of (4,4,3,3,3) this satisfies the condition of product 216
@shinoda said:
share ur approach
Adjust with my drawing skills..
@DeAdLy said:
Q1:

amit threw five standard dice simultaneously. He found that the product of the numbers on the top faces was 216. which of the following couldn't be the sum of numbers on top five faces:
a: 17
b: 19
c: 18
d: 20


Q2:

The number 2006! is written in base 22. How many zeroes are there at the end?
a: 500
b: 450
c: 200
d: 199


Q3:

X & Y are two natural no's such that X+Y=949. LCM of X & Y is 2628. What is the HCF of X & Y??
a: 23
b: 73
c: 69
d: none

Answer along with approach is must
for first
216=6*6*6*1 , 6*6*2*3*1 , 4*3*3*6*1
so it eliminates 20,18 and 17
so only 19 left which is not possible
for 2nd
for base 10 number of 0s depend on power of 5 so in base 22 it will depend on power of 11
so power of 11 in 2006! = 199 [2006/11]+[2006/121] +[2006/1331] where [] represents greatest integer
so 199
for 3rd one
2628 is 73*4*9
let number be of the form of 73x and 73y
x is 4 and y is 9
it satisfies giving sum = 949
so 73
@Dexian said:

iska sol batao na plzzz
triangles possible with all points
13c3 - 7c3 - 5c3 - 4c3 = 237
triangles which do not have a point common with a,b,c
10c3 - 5c3 - 3c3 = 109
237- 109= 128
but u have to subtract abc triangle from it too so
128 - 1 =127
@Estallar12 said:
So much spamming on Quant Thread ?
Move to SB.

Question:

A not-so-good clockmaker has four clocks on display in the window.
Clock #1 loses 15 minutes every hour.
Clock #2 gains 15 minutes every hour relative to Clock #1 (i.e., as Clock #1 moves from 12:00 to 1:00, Clock #2 moves from 12:00 to 1:15).
Clock #3 loses 20 minutes every hour relative to Clock #2.
Finally, Clock #4 gains 20 minutes every hour relative to Clock #3.

If the clockmaker resets all four clocks to the correct time at 12 noon, what time will Clock #4 display after 6 actual hours (when it is actually 6:00 pm that same day) ?


P.S. Spam Posts delete kar dena!
in 1 actual hour
clock 1 goes 45
clock 2 goes 75 when clock 1 goes 60 so when clock 1 goes 45 clock 2 goes 75*45/60=225/4
clock 3 goes 40 when clock 2 goes 60 so when clock 3 goes 225/4 then 40*225/4*60=75/2
clock 4 goes 80 when clock 3 goes 60 so when clock 3 goes 75/2 clock 4 goes 80*75/2*60=50
in 6 actual hours clock 4 goes 50*60=3000 min
3000/60=5 hours
so 5pm

If a,b,c are 3 non negative integers such that a+b+c=10, find the max value of ab+bc+ac+abc

@shinoda said:
Find the area of the traingle inscribed in a circle circumscribed by a square made by joining the mid points of the adjacent sides of a square of side 'A' ?
radius of circle = a/2root2
considering triangle is equilateral
area = 3_/3a^2/32
@maroof10 said:
If a,b,c are 3 non negative integers such that a+b+c=10, find the max value of ab+bc+ac+abc
69
4,4,3 se
@shinoda said:
Find the area of the traingle inscribed in a circle circumscribed by a square made by joining the mid points of the adjacent sides of a square of side 'A' ?
3rt3*a^2/32 ?