I am not sure if i can attach a file here. You have to PM me your mail id so that i can mail you those docs. And I already gave my GMAT last year 
Ok. Here I go...
1. How many 4-digit numbers can be formed by using the digits 0-9, so that no two digits are repeated?
(A) 4536 (B) 4546 (C) 4556 (D) 9436 (E) 9556
Solution:
Consider the LOVE 😃 (below) as a 4-digit number.
L O V E
L can be filled in 9 ways (excl 0)
O can be filled in 9 ways (This can contain 0. But, cannot contain the L digit 😃 )
V can be filled in 8 ways (similarly)
E can be filled in 7 ways.
Total 4 digit numbers: 9 X 9 X 8 X 7 = 4536
2. How many even 4-digit numbers can be formed by using the digits 0-9, so that no two digits are repeated?
(A) 2296 (B) 2396 (C) 2444 (D) 2456 (E) 2486
Solution:
Finding number of even 4-digit numbers becomes cumbersome.
So, let's find out the number of Odd 4-digits :)
Consider 'LOVE' to be 4 digit number.
E can be filled in 5 ways (either of 1,3,5,7,9)
L can be filled in 8 ways (excl. the number ZERO and the number E)
O can be filled in 8 ways (excl. L and E)
V can be filled in 7 ways (similarly)
Total number of odd 4-digit numbers: 8 X 8 X 7 X 5 = 2240.
Total number of 4-digit numbers (we know from Question 1) : 4536
Hence, total number of even 4-digit numbers is 4536 - 2240 = 2296
How many even 4-digit numbers divisible by 4 can be formed by using the digits 0-9, so that no two digits are repeated?
(A) 336 (B) 784 (C) 1120 (D) 1804 (E) 1936
Solution:
This was just a guess. Yet to find out the correct method of solving this.
Now, since the number of 4-digit even numbers was 2296, the number of 4-digit even numbers divisible by 4, should be approximately (though not exactly) half of 2296 (Since, the other half would be indivisible by 4 :)) which comes to 1148. Now, the closest solution is C, 1120 Kindly share, if anybody knows the exact procedure. :)
How many 4-digit numbers can be formed by using the digits 0-9, so that it contains exactly 3 distinct digits?
(A) 1944 (B) 3240 (C) 3850 (D) 3888 (E) 4216
Solution:
Let L O V E be the 4 digit number :)
L can be filled in 9 ways (excl. ZERO)
O can be filled in 9 ways (excl. L alone)
V can be filled in 8 ways (excl. L and O)
E can be filled in only 3 ways (b'coz, it has to take either of L, O, V, since there are exactly only 3 distinct digits. So, 4th digit repeats :))
So, the solution is 9 X 9 X 8 X 3 = 1944 :)
Hope this helped :)
euros SaysI have posted these questions here because I do not have the solutions or the answers.If I had the answers, I would have definitely posted them at the end of the post. Will appreciate if you could share the solutions. :)
My answers below
1. 4536
2. 2296
3. 1120
-Deepak.
Thank you very much ravisekharan. You have done a fantastic with the explanations.
Hi Deepak,
Since you have worked out the answers, I will appreciate if you could share the solutions too. Ravi has already posted his solutions. It will be great to know that theres another approach and that Ravi's answers are same as yours (since I do not have the OA's).
Thank you very much ravisekharan. You have done a fantastic with the explanations.
Hi Deepak,
Since you have worked out the answers, I will appreciate if you could share the solutions too. Ravi has already posted his solutions. It will be great to know that theres another approach and that Ravi's answers are same as yours (since I do not have the OA's).
Ravi's approach is exactly the same as mine.
-Deepak.
A jar contains 30 marbles, of which 20 are red and 10 are blue. If 9 of the marbles are removed, how many of the marbles left in the jar are red?
(1) Of the marbles removed, the ratio of the number of red ones to the number of blue ones is 2 : 1.
(2) Of the first 6 marbles removed, 4 are red.
A Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient.
B Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient.
C BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient.
D EACH Statement ALONE is sufficient.
E Statements (1) and (2) TOGETHER are NOT sufficient.
Option "A" is the correct one.
Last Friday a certain shop sold 3/4 of the sweaters in its inventory. Each sweater sold or $20. What was the total revenue last Friday from the sale of these sweaters?
(1) When the shop opened last Friday, there were 160 sweaters in its inventory.
(2) All but 40 sweaters in the shop's inventory were sold last Friday.
A Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient.
B Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient.
C BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient.
D EACH Statement ALONE is sufficient.
E Statements (1) and (2) TOGETHER are NOT sufficient.
Option "D" is the correct one
Please slove the following question,
pls help me out with the logic.
1)A,B,C complete a certain piece of work in 10,20,5 hours respectively.A alone works for the first 2 hours ,B and C the joined A ,and the three completed the rest of the work together .How long did it take to complete the task.??
Please slove the following question,
pls help me out with the logic.
1)A,B,C complete a certain piece of work in 10,20,5 hours respectively.A alone works for the first 2 hours ,B and C the joined A ,and the three completed the rest of the work together .How long did it take to complete the task.??
Lets first see rates for the three individuals - A, B & C
A's rate = 1/10 per hr
B's rate = 1/20 per hr
C's rate = 1/5 per hr
Combined rate of A, B, & C = (1/10) + (1/20) + (1/5) = 7/20 per hr
When A alone works for 2 hours, progress achieved = (1/10) x 2 = 1/5th work is completed.
The remaining work = 1- (1/5) = 4/5
Time required to finish remaining work by the three people combined:
(4/5) divided by (7/20) = 16/7 hrs
Total time taken = 2 + 16/7 = 30/7 = 4 & 2/7ths hours
Hope this matches the OA.
A man chooses an outfit from 3 different shirts, 2 different pairs of shoes, and 3 different pants. If he randomly selects 1 shirt, 1 pair of shoes, and 1 pair of pants each morning for 3 days, what is the probability that he wears the same pair of shoes each day, but that no other piece of clothing is repeated?
A) (1/3)^6 (1/2)^3
B) (1/3)^6 (1/2)
C) (1/3)^4
D) (1/3)^2 (1/2)
E) 5*(1/3)^2
How to approach such problems?
OA is (C)
Please slove the following question,
pls help me out with the logic.
1)A,B,C complete a certain piece of work in 10,20,5 hours respectively.A alone works for the first 2 hours ,B and C the joined A ,and the three completed the rest of the work together .How long did it take to complete the task.??
In 1-hr,A can complete 1/10 of the task.In 2 hrs, A can complete 1/5th of the task.
So,A+B+C are completing 4/5 th of the task.
In 1-hr A + B + C can complete 1/10 + 1/20 + 1/5 = 7/20 th of the task.
So they can complete 1 task in 20/7 hrs.
They will complete 4/5th of the task in 20/7 * 4/5 = 16/7 hrs.
Total time taken to complete the task is 16/7 + 2 = 30/7 hrs.
-Deepak.
A man chooses an outfit from 3 different shirts, 2 different pairs of shoes, and 3 different pants. If he randomly selects 1 shirt, 1 pair of shoes, and 1 pair of pants each morning for 3 days, what is the probability that he wears the same pair of shoes each day, but that no other piece of clothing is repeated?
A) (1/3)^6 (1/2)^3
B) (1/3)^6 (1/2)
C) (1/3)^4
D) (1/3)^2 (1/2)
E) 5*(1/3)^2
How to approach such problems?
OA is (C)
There are 2 ways of solving that I can think of:
Doing the Probability way:
P of choosing a new shirt, new pant, any shoe on Day 1 = 1*1*1
P of choosing a new shirt, new pant, same shoe on Day 2 = 2/3*2/3*1/2
P of choosing a new shirt, new pant, same shoe on Day 3 = 1/3*1/3*1/2
So the Probability for all three days is a product of individual probabilities.
1*(2/3*2/3*1/2)*(1/3*1/3*1/2) = (1/3)^4 (Answer Choice C)
Doing the combination way:
P = Favorable/Total
Favorable :
Day 1 - 3*3*1
Day 2 - 2*2*1
Day 3 - 1*1*1
This can be repeated with the other shoe so total cases are (9+4+1) + (9+4+1) = 28
Total cases =
Day 1 : 3*3*2
Day 2 : 3*3*2
Day 3 : 3*3*2
Total cases = 27*2
P = 28/27*2 = 14/27
So I guess solving this using Individual Probabilities is correct.
A sum of money P doubles in 10 years.In how many years it will be treble at same rate of simple interest?
Pls tell the logic no clue...
A sum of money P doubles in 10 years.In how many years it will be treble at same rate of simple interest?
Pls tell the logic no clue...
Is this all the information that the question provides?
If we assume that the question talks about straight line simple interest, then the rate of interest is 10% p.a. and the amount will treble in 20 yrs.
Am I missing something?
A sum of money P doubles in 10 years.In how many years it will be treble at same rate of simple interest?
Pls tell the logic no clue...
Assuming it as simple interest, we get r = 10%. So the amount of money will treble in 20 yrs.
-Deepak.
Please slove the following question,
pls help me out with the logic.
1)A,B,C complete a certain piece of work in 10,20,5 hours respectively.A alone works for the first 2 hours ,B and C the joined A ,and the three completed the rest of the work together .How long did it take to complete the task.??
Let's consider the work as "Binding 100 books :)"
Acc to Q,
A's ability - 10 books per hour
B's ability - 5 books per hours
C's ability - 20 books per hour
Total ability - 35 books per hour
* A alone works for the first 2 hours --> Completes 20 books.
* Reamining 80 books to be bound by all 3 together (having an ability of 35books/hour). So, in two hours they would complete 70 books.
* Remaining books - 10. So, it would take 10/35 (which is 2/7) hours to complete.
So, total hours 2+2+(2/7) = 4 and (2/7) hours or (30/7) hours.
Hope this helped 😃
Puys help me out in inequalities specially modulus...No clue how to approach the problem.any study material for it...and ya here is 1 question:-
1. X / X|
A. X > 1
B. X > -1
C. X D. X = 1
E.|X^2 > 1
Please explain the approach and solution?How to approach modulus inequality?
1. A password of a computer used five digits where they are from 0 and 9. What is the probability that the password solely consists of prime numbers and zero?
A 1/32
B 1/16
C 1/8
D 2/5
E
A 1/32
B 1/16
C 1/8
D 2/5
E
Just wanted to know from those guys who appeared in GMAT atleast once.Does the difficulty level of the Quant ques almost remain the same as given in the OG or do the ques which come in the actual GMAT difficult than those given?
Hii anu and everyone,
This is my first post on this blog. Regards your question. prime nos(2,3,5,7) and 0 presents 5 possibilities. since the question is abt password and not a 5 digit number and since there is no restriction on repetitions(see even 00000 could also be a pwd), there are total of 5^5 favorable ways. Total no of ways are 10^10. therefore ans is 5^5/10^10= 1/32
Hope my ans is correct,
regards-- vijay
Hii anu,
well typing mistake in my first post itself. Extremely sorry
Total no of ways are 10^5. therefore ans is 5^5/10^5= 1/32
regards-- vijay