The Official CAT 2007 Quant Thread

[80199]

Originally Posted by Hi2All
Hello friends...
A man spending half of his salary for house hold expenses, 1/4th for rent, 1/5th for travel expenses, a man deposits the rest in a bank. If his monthly deposits in the bank amount 50. What is his monthly salary?

How to approach this problem???

SOLN-:
Let his salary be X
than X - (X/2 +X/4 + X/5) = 50
solving this v get X= 1000

[80199]

Let x =
Then x equals

Choose one answer.
a. 3 b. (√13 -1)/2 c. (√13 + 1)/2 d. √13

solve it?

[stalwart_itsme]

Originally Posted by 80199

3 Marks: --/1

Two identical circles intersect so that their centers, and the points at which they intersect, form a square of side 1 cm. The area in sq. cm of the portion that is common to the two circles is:

Choose one answer.
a. p/4 b. p/2 -1 c. p/5 d. p/4 e. √2 -1

plz help me solving this

Let O and O' be the centers of the two identical triangles and A and B be the intersecting points. Now OO'AB is a unit square.

Now the area common to the circles is obtained by subtracting the area of the triangle OAB with the area of the sector OAB in the circles..

Area of the sector OAB = pi/4
area of the triangle OAB = 1/2

so common area is = [pi/4 -1/2]*2 ... ( it is mutiplied by 2 since we get only one of the common area after subtracting)

so area is [pi/2 - 1] .. option b

[parmindersaluja]

Originally Posted by 80199

Originally Posted by Hi2All
Hello friends...
A man spending half of his salary for house hold expenses, 1/4th for rent, 1/5th for travel expenses, a man deposits the rest in a bank. If his monthly deposits in the bank amount 50. What is his monthly salary?

How to approach this problem???

SOLN-:
Let his salary be X
than X - (X/2 +X/4 + X/5) = 50
solving this v get X= 1000

100% - (50% + 25% + 20%) = 50

5% = 50
=> 100% = 1000

[getneonow]

Originally Posted by 80199

Let x =
Then x equals

Choose one answer.
a. 3 b. (√13 -1)/2 c. (√13 + 1)/2 d. √13

solve it?

The qn can easily be misinterpreted in ur notation but i think this is wat u r asking

x = sq.rt(4+ sq.rt(4-x))

when we try to solve this we may land up in some extraneous solutions like 3 but by common sense we can eliminate such options.

The value of x clearly shud lie just above 2 and can't be greater than 3.

so the ans is C

Neo

[gautamgomzi]

Q. ) Two pipes can fill a cistern in 14 and 16 hrs respectively. The pipes are opened simultaneously, but due to a leakage it takes 32 minutes extra to fill up the cistern. When the cistern is full in what time will the leak empty it????

ANS- 112 hours


Q.) Two typists of varying skills can do a job in 6 min if they work together. If the first typist typed alone for 4 minutes and the second typist typed alone for 6 minutes, they would be left with 1/5 of the whole work. How many minutes would it take the slow typist to complete the job alone???


ANS – 15 minutes


Q.) Three cooks have to make 80 idlis.They are known to make 20 idlis. The first cook began working alone and and made 20 pieces having worked for sumtime more than 3 minutes. The remaining part of the work was done by the 2nd and the 3rd cook working together. It took a total of 8 minutes to complete the 80 idlis. How many minutes would it take the first cook alone to cook 160 idlis for the party the next day??

ANS – 32 minutes


Q.) It takes 6 days for three women and two men working together to complete a work. Three men would do the same work five days sooner than 9 women. How many times the output of a man exceed that of a woman ??

a. 3 times b.4times c. 5times d. 6times e. 7 times



plz solve these ques...

Thnx..GAUTAM

[dashing]

Originally Posted by gautamgomzi

Q. ) Two pipes can fill a cistern in 14 and 16 hrs respectively. The pipes are opened simultaneously, but due to a leakage it takes 32 minutes extra to fill up the cistern. When the cistern is full in what time will the leak empty it????

ANS- 112 hours


Q.) Two typists of varying skills can do a job in 6 min if they work together. If the first typist typed alone for 4 minutes and the second typist typed alone for 6 minutes, they would be left with 1/5 of the whole work. How many minutes would it take the slow typist to complete the job alone???


ANS – 15 minutes


Q.) Three cooks have to make 80 idlis.They are known to make 20 idlis. The first cook began working alone and and made 20 pieces having worked for sumtime more than 3 minutes. The remaining part of the work was done by the 2nd and the 3rd cook working together. It took a total of 8 minutes to complete the 80 idlis. How many minutes would it take the first cook alone to cook 160 idlis for the party the next day??

ANS – 32 minutes


Q.) It takes 6 days for three women and two men working together to complete a work. Three men would do the same work five days sooner than 9 women. How many times the output of a man exceed that of a woman ??

a. 3 times b.4times c. 5times d. 6times e. 7 times



plz solve these ques...

Thnx..GAUTAM

Q. ) Two pipes can fill a cistern in 14 and 16 hrs respectively. The pipes are opened simultaneously, but due to a leakage it takes 32 minutes extra to fill up the cistern. When the cistern is full in what time will the leak empty it????

Answer

two pipes can fill together in 112/15 hrs
with the leak they need 8 hrs

so
1/14 + 1/16 -1/x = 1/8
x = 112

Q.) Two typists of varying skills can do a job in 6 min if they work together. If the first typist typed alone for 4 minutes and the second typist typed alone for 6 minutes, they would be left with 1/5 of the whole work. How many minutes would it take the slow typist to complete the job alone???

Answer ---
1/a + 1/b = 1/6
=> ab = 6(a+b)

4b+6a)/ab = 4/5

Solving these two
a= 10
b = 10

Q.) Three cooks have to make 80 idlis.They are known to make 20 idlis. The first cook began working alone and and made 20 pieces having worked for sumtime more than 3 minutes. The remaining part of the work was done by the 2nd and the 3rd cook working together. It took a total of 8 minutes to complete the 80 idlis. How many minutes would it take the first cook alone to cook 160 idlis for the party the next day??

Answer -- Not able to understand
May be some data is missing

Q.) It takes 6 days for three women and two men working together to complete a work. Three men would do the same work five days sooner than 9 women. How many times the output of a man exceed that of a woman ??

Answer ---
3w + 2m = 1/6
9w - 3m = 1/5

3 times

[dashing]

Originally Posted by gautamgomzi

Q. ) Two pipes can fill a cistern in 14 and 16 hrs respectively. The pipes are opened simultaneously, but due to a leakage it takes 32 minutes extra to fill up the cistern. When the cistern is full in what time will the leak empty it????

ANS- 112 hours


Q.) Two typists of varying skills can do a job in 6 min if they work together. If the first typist typed alone for 4 minutes and the second typist typed alone for 6 minutes, they would be left with 1/5 of the whole work. How many minutes would it take the slow typist to complete the job alone???


ANS – 15 minutes


Q.) Three cooks have to make 80 idlis.They are known to make 20 idlis. The first cook began working alone and and made 20 pieces having worked for sumtime more than 3 minutes. The remaining part of the work was done by the 2nd and the 3rd cook working together. It took a total of 8 minutes to complete the 80 idlis. How many minutes would it take the first cook alone to cook 160 idlis for the party the next day??

ANS – 32 minutes


Q.) It takes 6 days for three women and two men working together to complete a work. Three men would do the same work five days sooner than 9 women. How many times the output of a man exceed that of a woman ??

a. 3 times b.4times c. 5times d. 6times e. 7 times



plz solve these ques...

Thnx..GAUTAM

Q. ) Two pipes can fill a cistern in 14 and 16 hrs respectively. The pipes are opened simultaneously, but due to a leakage it takes 32 minutes extra to fill up the cistern. When the cistern is full in what time will the leak empty it????

Answer

two pipes can fill together in 112/15 hrs
with the leak they need 8 hrs

so
1/14 + 1/16 -1/x = 1/8
x = 112

Q.) Two typists of varying skills can do a job in 6 min if they work together. If the first typist typed alone for 4 minutes and the second typist typed alone for 6 minutes, they would be left with 1/5 of the whole work. How many minutes would it take the slow typist to complete the job alone???

Answer ---
1/a + 1/b = 1/6
=> ab = 6(a+b)

4b+6a)/ab = 4/5

Solving these two
a= 10
b = 10

Q.) Three cooks have to make 80 idlis.They are known to make 20 idlis. The first cook began working alone and and made 20 pieces having worked for sumtime more than 3 minutes. The remaining part of the work was done by the 2nd and the 3rd cook working together. It took a total of 8 minutes to complete the 80 idlis. How many minutes would it take the first cook alone to cook 160 idlis for the party the next day??

Answer -- Not able to understand
May be some data is missing

Q.) It takes 6 days for three women and two men working together to complete a work. Three men would do the same work five days sooner than 9 women. How many times the output of a man exceed that of a woman ??

Answer ---
3w + 2m = 1/6
9w - 3m = 1/5

3 times

[IIM maniac]

Hey Dashing dude,
you worte this ::Q. ) Two pipes can fill a cistern in 14 and 16 hrs respectively. The pipes are opened simultaneously, but due to a leakage it takes 32 minutes extra to fill up the cistern. When the cistern is full in what time will the leak empty it???? Answertwo pipes can fill together in 112/15 hrswith the leak they need 8 hrsso1/14 + 1/16 -1/x = 1/8x = 112
I wolud like to know from where did you get this 8 hrs with the leak?
even though my query sounds pitty..

[dashing]

Originally Posted by IIM maniac

Hey Dashing dude,
you worte this ::Q. ) Two pipes can fill a cistern in 14 and 16 hrs respectively. The pipes are opened simultaneously, but due to a leakage it takes 32 minutes extra to fill up the cistern. When the cistern is full in what time will the leak empty it???? Answertwo pipes can fill together in 112/15 hrswith the leak they need 8 hrsso1/14 + 1/16 -1/x = 1/8x = 112
I wolud like to know from where did you get this 8 hrs with the leak?
even though my query sounds pitty..

Hi

Without leak its 112/15 hrs
With leak its 112/15 + 32/60 => 112/15 + 8/15 => 120/15 => 8