This results when you flip the numerator and denominator of a fraction. what do you call this?

Ivan and jeff buy a package of 8 pens for $4.00. ivan wants 5 of the pens, and jeff wants 3.how much should each student pay?

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?

How many lines can be drawn through points j and k? 0 1 2 3