Search found 14 matches
(a + b)(a - b) = (a + b)(a - b) = a² - b². Step 1: (2² + 1)(2² - 1) (2� + 1)(2� + 1) (2� - 1) (2� + 1)(2� + 1). Step 2: (2� - 1)(2� + 1) (2� + 1). (2� - 1) (2� + 1). Step 3: (2� - 1)(2� + 1) 2¹� - 1 . The correct answer is A . Ohhh! I see my mistake. I never went beyo...
- by Halimah_O
Fri Dec 23, 2016 4:56 am- Forum: Problem Solving
- Topic: Please what's the way out here? I'm def missing something
- Replies: 6
- Views: 3295
Please what's the way out here? I'm def missing something
I can seem to wrap my head around this one. I tried simplifying... too long. I tried working with units digits... didn't quite work out.
Please I need experts to shine some light here.
Thank you.
OA: A
- by Halimah_O
Fri Dec 23, 2016 3:54 am- Forum: Problem Solving
- Topic: Please what's the way out here? I'm def missing something
- Replies: 6
- Views: 3295
The shaded region in the figure below represents a rectangular frame with length 18 inches and width 15 inches. The frame encloses a rectangular picture that has the same area as the frame itself. If the length and width of the picture have the same ratio as the lenght and width of the frame, what ...
- by Halimah_O
Sat Dec 10, 2016 1:21 am- Forum: Problem Solving
- Topic: The shaded region in the figure above represents a rectangul
- Replies: 4
- Views: 7854
In a shipment of 20 cars, 3 are found to be defective. If 4 cars are selected at random, what is the probability that exactly one of the four will be defective? (a) 170/1615 (b) 3/20 (c) 8/19 (d) 3/5 (e) 4/5 Let D = defective and N = not defective. P(exactly n times) = P(one way) * total possible w...
- by Halimah_O
Mon Dec 05, 2016 9:29 am- Forum: Problem Solving
- Topic: Hard Probability
- Replies: 6
- Views: 3157
Probability... again
A certain bag of gemstones is composed of two-thirds diamonds and one-third rubies. If the probability of randomly selecting two diamonds from the bag, without replacement is 5/12, what is the probability of selecting two rubies from the bag, without replacement. (a) 5/36 (b) 5/24 (c) 1/12 (d) 1/6 (...
- by Halimah_O
Mon Dec 05, 2016 6:35 am- Forum: Problem Solving
- Topic: Probability... again
- Replies: 7
- Views: 3269
Hard Probability
In a shipment of 20 cars, 3 are found to be defective. If 4 cars are selected at random, what is the probability that exactly one of the four will be defective?
(a) 170/1615
(b) 3/20
(c) 8/19
(d) 3/5
(e) 4/5
- by Halimah_O
Mon Dec 05, 2016 6:30 am- Forum: Problem Solving
- Topic: Hard Probability
- Replies: 6
- Views: 3157
If Mark saved an average (arithmetic mean) of $80 per week for 3 consecutive weeks, how much did he save the second week? (1) The average amount that Mark saved per week for the first 2 weeks was $60. (2) The amount that Mark saved the first week was 1/2 the amount he saved the second week and 1/3 ...
- by Halimah_O
Tue Nov 22, 2016 4:36 am- Forum: Data Sufficiency
- Topic: This took me longer than 2 mins :(
- Replies: 4
- Views: 2245
This took me longer than 2 mins :(
If Mark saved an average (arithmetic mean) of $80 per week for 3 consecutive weeks, how much did he save the second week? (1) The average amount that Mark saved per week for the first 2 weeks was $60. (2) The amount that Mark saved the first week was 1/2 the amount he saved the second week and 1/3 t...
- by Halimah_O
Tue Nov 22, 2016 3:43 am- Forum: Data Sufficiency
- Topic: This took me longer than 2 mins :(
- Replies: 4
- Views: 2245
AWA Essay - Manhattan CAT 3 - Please assist to review
ESSAY QUESTION: The following appeared in the editorial section of a local newspaper: “The inflow of immigrant workers into our community has put a downward pressure on wages. In fact, the average compensation of unskilled labor in our city has declined by nearly 10% over the past 5 years. Therefo...
- by Halimah_O
Mon Sep 12, 2016 4:53 am- Forum: GMAT Essays (AWA)
- Topic: AWA Essay - Manhattan CAT 3 - Please assist to review
- Replies: 0
- Views: 1484
AWA Essay - Manhattan CAT2 - Please Review
ESSAY QUESTION: The following appeared in a medical magazine: "Art and music have long been understood to have therapeutic effects for individuals who suffer from either physical or mental illnesses. However, most doctors rarely recommend to patients some form of art or music therapy. Instead, ...
- by Halimah_O
Sun Sep 11, 2016 10:26 pm- Forum: GMAT Essays (AWA)
- Topic: AWA Essay - Manhattan CAT2 - Please Review
- Replies: 0
- Views: 1211
People always try putting value to validate the the given conditions but somehow I like the algebraic way. w=y-z given St 1) y+z is a perfect square ----> assume it as k^2 therefore y = k^2 - z and substitute this condition in w w = k^2 -2z here w may or may not be a perfect square depending on the...
- by Halimah_O
Wed Aug 17, 2016 4:07 am- Forum: Data Sufficiency
- Topic: W, Y and Z; Integer Properties
- Replies: 4
- Views: 1580
W, Y and Z; Integer Properties
If w, y and z are positive integers, and w = y - z, is w a perfect square?
I. y+z is a perfect square
II. z is even
I chose E.
Dear experts please assist with explanation in this.
Thank you
- by Halimah_O
Wed Aug 17, 2016 1:16 am- Forum: Data Sufficiency
- Topic: W, Y and Z; Integer Properties
- Replies: 4
- Views: 1580
Integer Properties - I need expert help please
What is the three-digit number abc, given that a, b and c are the positive single digits that make up the number?
I. a=1.5b and b=1.5c
II. a=1.5x + b and b=x+c, where x represents a positive single digit.
I chose A but I need expert opinion.
- by Halimah_O
Wed Aug 17, 2016 1:02 am- Forum: Data Sufficiency
- Topic: Integer Properties - I need expert help please
- Replies: 3
- Views: 1155
Confusing Arithmetic Problem
Please I need help with this, If money is invested at r percent interest, compounded annually, the amount of the investment will double in approximately 70/r years. If Pat's parents invested $5000 in a long term bond that pays 8 percent interest, compounded annually, what will be the approximate tot...
- by Halimah_O
Sat Feb 06, 2016 10:32 am- Forum: GMAT Math
- Topic: Confusing Arithmetic Problem
- Replies: 2
- Views: 3202