Function - Set30Q2

The function f is defined for each positive three-digit integer n by f(n) = 2^x3^y5^z, where x, y and z are the hundreds, tens, and units digits of n, respectively. If m and v are three-digit positive integers such that f(m) = 9f(v), then m-v = ? A. 8 B. 9 C. 18 D. 20 E. 80 Please explain. Thanks. O...

Integers

Both a, b, and c are 3-digits integers, where a=b+c. Is the hundreds' digit of number a equal to sum of that of b and c?

1). Tens' digit of a=tens' digit of b+tens' digit of c
2). Units' digit of a=units' digit of b + units' digit of c

OA- E

line intersection

Line K's slope is positive and L's is negative. Is K's intersection point with axis-y above that of L?

1). K's intersection point with axis-x is to the left of the origin.
2). K's intersection point with axis-y is above the origin.

OA - E

coordinate

Q1. Does Y=mX^2+h intersect with axis-x?

1). m<0
2). h>0

OA - C

Q2. Y=a(x-b)^2+P. Can you tell if y intersects with x axis?
1). a<0
2). P>0

OA - C

I guess both the questions use the same approach. Pls explain. Thanks.

Coordinates - circle

The circle has center O and radius 50, and point P has coordinates (50,0). If point Q is on the circle, what is the length of line segment PQ? (1) The x-coordinate of point Q is -30. (2) The y-coordinate of point Q is -40. [spoiler]OA - E. IMO - C...it says on the circle not anywhere in the circle.....

multiples

If 500 is the multiple of 100 that is closest to X and 400 is the multiple of 100 that is closest to Y, which multiple of 100 is closest to X +Y ?

1). X is less than 500
2). Y is less than 400

OA - E

The Federal Reserve Board’s reduction of interest rates on loans to financial institutions is both an acknowledgment of past economic trends and an effort to influence their future direction.

Their refers to the past economic trends - so it has to be plural.

Functions

If f(x) = x-x^2 is f(a)<f(b)?

1). a<b
2). a^2< b^2

OA - E