Search found 20 matches
- by keizer Soze
Sun May 03, 2009 11:35 am- Forum: Problem Solving
- Topic: (5^11) . 4^10 = 2 . 10^n
- Replies: 4
- Views: 1452
I solved it this way: 5^11 . 4^10 = 2 . 10^n 5^11 . 2^19 = 10^n 10^11 . 2^8 = 10^n 10^11 . 2^8 . 5^8/5^8 = 10^n 10^19 . 1/5^8 = 10^n (A) Here: 5^8= 10^8 . 1/2^8 (B) 2^10=~ 10^3............ so, 2^8 =~ 10^2,4 Again in (B): 5^8 = 10^8 / 10^2,4 = 10^5,6 Finally in (A): 10^19 / 10^5,6 =~ 10^n 10^13,4 =~ ...
- by keizer Soze
Sun May 03, 2009 11:33 am- Forum: Problem Solving
- Topic: (5^11) . 4^10 = 2 . 10^n
- Replies: 4
- Views: 1452
- by keizer Soze
Sun May 03, 2009 10:56 am- Forum: Problem Solving
- Topic: (5^11) . 4^10 = 2 . 10^n
- Replies: 4
- Views: 1452
- by keizer Soze
Sat May 02, 2009 10:31 am- Forum: Problem Solving
- Topic: please explain how to solve it.
- Replies: 13
- Views: 3146
- by keizer Soze
Sat May 02, 2009 10:08 am- Forum: Problem Solving
- Topic: please explain how to solve it.
- Replies: 13
- Views: 3146
- by keizer Soze
Sat May 02, 2009 9:05 am- Forum: Problem Solving
- Topic: Tricky root of a square
- Replies: 2
- Views: 1257
- by keizer Soze
Sat May 02, 2009 8:24 am- Forum: Problem Solving
- Topic: Tricky root of a square
- Replies: 2
- Views: 1257
- by keizer Soze
Fri May 01, 2009 3:54 pm- Forum: Data Sufficiency
- Topic: Absolute Value
- Replies: 2
- Views: 946
Absolute Value
I need to find a shortcut for this one (I searched it but I couldn´t find it):
If a and b are integers, and |a| > |b|, is a · |b| < a – b?
(1) a < 0
(2) ab >= 0
OA E
- by keizer Soze
Fri May 01, 2009 3:17 pm- Forum: Data Sufficiency
- Topic: Absolute Value
- Replies: 2
- Views: 946
C is a posibility, but there Y could be any other number, and the question asked which MUST be true... you can´t be sure that y=1... it could be y=2 or y=3...
- by keizer Soze
Thu Apr 30, 2009 8:07 am- Forum: Problem Solving
- Topic: Algebra question
- Replies: 4
- Views: 1268
Ok doofus, it´s good to know that!
The last one: can I round up a number when I have other solutions that are not integers?
- by keizer Soze
Thu Apr 30, 2009 5:01 am- Forum: Problem Solving
- Topic: Simple Interest
- Replies: 11
- Views: 1834
- by keizer Soze
Wed Apr 29, 2009 8:20 pm- Forum: Problem Solving
- Topic: Circle and Chord
- Replies: 5
- Views: 1726
Circle and Chord
Any ideas how to solve this? I couldn´t, don´t know if it´s right.
Circle X has chord AB that intersects radius XC in point D and angle XDB is 90°. If AB=12 and DC=2. What is the circumference of the circle?
[spoiler]20 ∏[/spoiler]
- by keizer Soze
Wed Apr 29, 2009 7:34 pm- Forum: Problem Solving
- Topic: Circle and Chord
- Replies: 5
- Views: 1726
The last equation is z=zx
so here x=1 and z must be 0
y could be 0 also, but it musn´t be 0, it could be any other number. I think that there is the key.
- by keizer Soze
Wed Apr 29, 2009 7:26 pm- Forum: Problem Solving
- Topic: Algebra question
- Replies: 4
- Views: 1268
Hi
doofus, why do you assume that the period of the rate is one year (12 month)?
You would be alright if the question asked the "12 month rate" ... but in this case i´m not sure, correct me if i´m wrong.
- by keizer Soze
Wed Apr 29, 2009 3:58 pm- Forum: Problem Solving
- Topic: Simple Interest
- Replies: 11
- Views: 1834