Question

A newly made car will have a model number, a parts number, and a serial number. A model number is assigned by the manufacturer to identify each type of car. A parts number identifies one part of the smaller parts that make up the car. A serial number is unique to each car produced and identifies it.

Which relation is a function?

(parts number, serial number)

(model number, parts number)

(serial number, model number)

(serial number, part number)
Consider the two groups listed below. Which statement describes the sets?


the length of a swimming pool
the liquid volume of the pool
The relation (length, volume) is a function, but the relation (volume, length) is not.

The relation (volume, length) is a function, but the relation (length, volume) is not.

Both the relation (length, volume) and the relation (volume, length) are functions.

Neither the relation (length, volume) nor the relation (volume, length) is a function.

Answer 1

C. (Serial number, model number)

"A function relates an input to an output. It is like a machine that has an input and an output and the output is related somehow to the input".

Because the serial number is unique, if you input the serial number to function C, it will output the model number of the car.

Answer 2

1. The function is C. (serial number, model number) since each serial number has a certain model number.

2. The answer is D. Neither the relation (length, volume) nor the relation (volume, length) is a function. Other variables are needed in solving for the volume not only the length so the relation isn't a function.

A function is where every element in the domain is included and one input is related to only one output.