Search found 15 matches
How to solve this
For all integers n \geq 1, which of the following is divisible by 9?
(a) 8^n+1
(b) 4^n-3n-1
(c) 3^2^n+3n+1
(d) 10^n+1
- by zareentaj
Thu Aug 12, 2010 2:16 am- Forum: Problem Solving
- Topic: How to solve this
- Replies: 1
- Views: 914
Thanks Asif.Can you explain step by step.Asif wrote:Lets say together their rate is x hours.
1/(x+20) + 1/(x+5) = 1/x
Solving for x we get x= +10 or -10 (we shall take +10)
now the ratio is (10+20)/(10+5) = 2/1
thus its B.
- by zareentaj
Thu Aug 12, 2010 12:29 am- Forum: Problem Solving
- Topic: Work rate
- Replies: 30
- Views: 15511
- by zareentaj
Thu Aug 12, 2010 12:16 am- Forum: Problem Solving
- Topic: One Solution
- Replies: 2
- Views: 959
Thanks.4GMAT_Mumbai wrote:Hi,
Unlikely to be GMAT level ...
x - 3 = (2/(3+sqrt{7})) - 3
= (-7-3sqrt(7))/(3+sqrt(7))
Squaring the previous term will lead to 7.
- by zareentaj
Wed Aug 11, 2010 5:42 am- Forum: Problem Solving
- Topic: challenging ps for me......
- Replies: 7
- Views: 1460
The question stem tells us that x, y and z are positive integers. My approach is to focus on 3x=4y=7z. Since the variables are integers, 3x, 4y and 7z must also be integers. They all equal some mystery number. This mystery number is a multiple of 3, 4 and 7. The smallest values of x, y, z will resu...
- by zareentaj
Wed Aug 11, 2010 4:41 am- Forum: Problem Solving
- Topic: Sum of integers....Please help
- Replies: 4
- Views: 1584
Hi Alone... How did you come up with these smart numbers guess. i had troubling selecting the right numbers which satisfies both the equations. is there any technique to do that Hi, Alone simply picked a nice simply value for k, then solved the two equations with k=2. Plugging in: x + 2y = 7 2x + y...
- by zareentaj
Wed Aug 11, 2010 4:36 am- Forum: Problem Solving
- Topic: Solve for x - y
- Replies: 6
- Views: 1883
Thank you VS2013.VS2013 wrote:For the greatest possible value of x, y^4 must be 0.
Therefore, x^4=100= 10*10
Since 3*3=9, then x is slightly greater than 3.
Therefore, answer is b, 3-6.
- by zareentaj
Wed Aug 11, 2010 4:26 am- Forum: Problem Solving
- Topic: Exponents and Estimating
- Replies: 6
- Views: 1610
Number of quadratic expressions
The number of quadratic expressions with the coefficient drawn from the set{0,1,2,3} is:
(a)21
(b)36
(c)48
(d)64
- by zareentaj
Tue Aug 10, 2010 10:16 pm- Forum: Problem Solving
- Topic: Number of quadratic expressions
- Replies: 1
- Views: 959
i got B-30 reasoning at first let us find the point where line y=3x+15 intersect with the circle x^2+y^2=5^2 with radiu=5 ( as circle with the center in the origin is given wiith the equation x^2+y^2=R^2) x^2+(3x+15)^2=25 solving and simplifing x^2+9x+20=0 x1=-5,x2=-4. we need here x2=-4. ( as -5 a...
- by zareentaj
Mon Aug 09, 2010 11:16 pm- Forum: Problem Solving
- Topic: Rectangle inscribed in a circle
- Replies: 4
- Views: 3354
total there will be three cases 55X -- in this case X can be replace with 9 other digits so 9 number of cases possible 5X5 -- in this case X can be replace with 9 other digits so 9 number of cases possible X55 -- in this case X can be replace with 8 other digits so 8 number of cases possible {first...
- by zareentaj
Mon Aug 09, 2010 11:01 pm- Forum: Problem Solving
- Topic: Permutation Problem
- Replies: 5
- Views: 1128
The centre of circle which touch the y-axis at (0,3) and making an intercept of 2 units on the positive x-axis, is: (a) (10,sqrt{3}) (b) (sqrt{3},10) (c) (sqrt{10},3) (d) (3,sqrt{10}) It is given that the circle touches the y-axes at (0,3) Which means y-axis is perpendicular to the line drawn from ...
- by zareentaj
Mon Aug 09, 2010 10:10 pm- Forum: Problem Solving
- Topic: how to solve this question
- Replies: 4
- Views: 1302
how to solve this question
The centre of circle which touch the y-axis at (0,3) and making an intercept of 2 units on the positive x-axis, is:
(a) (10,sqrt{3})
(b) (sqrt{3},10)
(c) (sqrt{10},3)
(d) (3,sqrt{10})
- by zareentaj
Mon Aug 09, 2010 9:17 pm- Forum: Problem Solving
- Topic: how to solve this question
- Replies: 4
- Views: 1302
- by zareentaj
Mon Aug 09, 2010 3:02 am- Forum: Problem Solving
- Topic: How to solve this problem
- Replies: 6
- Views: 4164
How to solve this problem
In how many ways can a mixed doubles game in tennis be arranged from 5 married couples, if no husband and wife play in the same game?
- by zareentaj
Sun Aug 08, 2010 10:18 pm- Forum: Problem Solving
- Topic: How to solve this problem
- Replies: 6
- Views: 4164
Tricky problem , but unable to solve this
How many different 7 digit members are their sum of whose digits is even ?
- by zareentaj
Sat Aug 07, 2010 5:35 am- Forum: Problem Solving
- Topic: Tricky problem , but unable to solve this
- Replies: 1
- Views: 849