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#51 Re: Help Me ! » Intrests » 2010-07-05 05:20:54
You're RIGHT Soroban about the Convention!! 
#53 Re: Puzzles and Games » Add 13 more and post it forever. » 2010-07-05 02:00:28
8684
#54 Re: Puzzles and Games » Add 13 more and post it forever. » 2010-07-04 22:21:48
8359
85931 is the 8359[sup]th[/sup] Prime number.
#55 Re: Puzzles and Games » Add 13 more and post it forever. » 2010-07-04 20:04:09
8294
#56 Re: Puzzles and Games » Catch Me If You Can! » 2010-07-04 19:33:41
2. What are the "next three terms" in the following sequence?
Z H H Z H Z H Z Z Z H Z H Z ? ? ?
#57 Re: Help Me ! » Intrests » 2010-07-04 16:47:58
Hi atut!
The question should mention that "9.6% per annum compounded quarterly" for that too work.
Anyways, I think that 9.6% interest quarterly is equivalent to 38.4% per annum which is too much hence take it to be 9.6% per annum!
#59 Re: Help Me ! » Intrests » 2010-07-04 05:36:07
Interest = 49700[(1 + 0.096)[sup]13[/sup] - 1]
#60 Re: Help Me ! » Area in km square ? » 2010-07-04 05:33:01
Just a little trick..
Hint: 200m=0.2km
Now you can proceed in the same way as you did for the Triangle!
#61 Re: Help Me ! » Help Needed » 2010-07-04 05:30:22
Yeah Mr. Khan!
That's perfectly all right! Even looks cool... Neat! 
#62 Re: Help Me ! » Help Needed » 2010-07-04 03:10:14
Just find the area of the triangle using...
Area=(Base*Height)/2
Now since the sides of the two triangles (the scaled down triangle and the actual larger triangle) are in the ratio 1cm:3km or 1cm:300000cm, the areas will be in the ratio 1²:300000². So multiply the area that you got above with 30000². Your answer will now be in cm². Change it to km².
#63 Re: Exercises » Selected Olympiad Questions! » 2010-07-04 03:00:14
Hi phrontister!
There's no logical method known to me to find those 3, 4, 5 and 6 digit Ns. 
Your computer program is certainly better and faster too!
#64 Re: Puzzles and Games » Euclidean Geometry » 2010-07-03 04:02:20
That is one of (the so called "easier" one) the "toughest easy geometry problems" of this world. I don't know who composed it but the solution does take a lot of constructions. I couldn't solve it on my own! 
#65 Re: Exercises » Selected Olympiad Questions! » 2010-07-02 21:05:42
I'd been hoping I'd got it right.
By all means! When I asked my colleagues this questions and found a mismatch, I told them that the correct answer has to be for the reasons you can understand! 
The method they used was....
#67 Re: Exercises » Selected Olympiad Questions! » 2010-07-02 03:25:03
Hi phrontister!
Sorry for the delay! I did not forget bout it but just was a little bit messed up on somethings. I gave the problem to two of my workmates and they came up with as the total number of numbers possible. The latter one had missed on a few numbers!!
Your solution is flawless!
You Rock!
#68 Re: Introductions » Factors » 2010-06-30 18:32:59
In general...
If a number N has prime factorization as follows...
N=a[sup]p[/sup]×b[sup]q[/sup]×c[sup]r[/sup]...
Then the number of distinct factors, including 1 and N is given by...
Number of Factors = (p+1)(q+1)(r+1)...
Here, 1176 = 2[sup]3[/sup]×3[sup]1[/sup]×7[sup]2[/sup]
∴ Number of factors = (3+1)(1+1)(2+1) = 24
#69 Re: Help Me ! » Help Needed » 2010-06-30 06:17:28
The answer will be (2 000 000×300)÷480
#70 Re: Help Me ! » Use the compound interest formula » 2010-06-30 06:12:06
The formula for the amount (A) accumulated over a period of N months on a principle P invested at R% compound interest compounded monthly is..
A=P(1+R)[sup]N[/sup]
Just plugin the values and find A.
Note that R here is to be taken as 0.1 or 1/10 and that N will be in months i.e. 20×12 months!
#71 Re: Introductions » Problem#3 Grade 11 Geometry » 2010-06-29 03:58:24
Yea.. The triangles are "similar" and not "congruent".
Its means that all their angles are equal and their sides are "proportional".
#72 Re: Help Me ! » Ratio answer confirmation » 2010-06-29 00:41:39
Probably not.
One of the "B+D" should be "A+D".
#73 Re: Exercises » Selected Olympiad Questions! » 2010-06-27 02:33:48
Awesome job!
I'll need to verify the answer to first part and for the second part perhaps "n" is standing upon its head?
#74 Re: Exercises » Selected Olympiad Questions! » 2010-06-26 17:46:49
You got it! In 4 (a), the actual statement "all the n-digits are different" actually means that "all digits of N are different".
You might have considered it as "1-digit N, 2-digit N, 7-digit N etc." where all "n"s are different. Instead, consider it as "4-digit N: 1234, 3456, 4567" where "all the 4-digits" of N are distinct.
For 3, its a Power Tower. 2 is raised by 1001 two's and 3 is raised by 1000 three's. You don't start counting from the "base" of the exponent in counting 1001/1000.
Thus, 2² has 2 raised to 2, 1 times.
Is the explanation good?
#75 Re: Exercises » Selected Olympiad Questions! » 2010-06-26 00:08:03
4. Suppose N is an n-digit positive integer such that
(a) all the n-digits are distinct.
(b) the sum of any three consecutive digits of N is divisible by 5.
How many such N's exist? What is the maximum value of 'n'?