Search found 3 matches
Question 1. We have the length of wire used to form a circle is circumference of the circle which means 2*pi*r, so the remains of wire used to form a square is (40 - 2*pi*r). The area of the circle is pi*r^2 and the square is (40 - 2*pi*r)^2. It means that represent the total area of the circular an...
- by chuongbill
Thu Dec 06, 2007 7:53 am- Forum: Problem Solving
- Topic: help needed!
- Replies: 6
- Views: 2180
Let me explain the answer for you,
The equation X(X-1)=380 is equivalent to
X^2-X-380=0
This is a square equation, so you can easily solve this for X and get two root, 20 and -19.
Since -19 is a negative number, so the correct answer must be A:20
- by chuongbill
Thu Dec 06, 2007 6:28 am- Forum: Problem Solving
- Topic: GMAT Prep
- Replies: 1
- Views: 1522
- by chuongbill
Thu Dec 06, 2007 5:27 am- Forum: Problem Solving
- Topic: DON'T UNDERSTAND
- Replies: 7
- Views: 1990