The ratio of DE to EF is 2:3

International calls require the use of a country code. many country codes a 3-digit numbers. country codes do not begin with a 0 or 1. there are no restrictions on the second and third digits. how many different 3-digit country codes are possible?

Two variables, x and y, vary inversely, and x=12 when y=4. what is the value of y when x=3?

How do you write y-10=2 (x-8) in standard form