define a variable to represent a real life quantity, such as length in centimeters or money in cents. then use the variable to write a mathematical expression to represent one of your daily activities. describe in words what your expression represents and explain your reasoning.

Answer 1

Well, one example could be

Velocity in m/s, km/h, etc...

You could use the equation: D=v/t
and say that it's used in daily life to calculate...

Speed, while also determining time and distance for engineering.

Answer 2

Another variable could be tax, which is also in money..

Ex: y = 0.15x + x
Where 0.15 is the tax % and x is the price of the product. This will tell you have much more you will have to pay on the store value.