Which of the following sets is closed under subtraction? a.) integers, b.) whole

The answer is Integers just took the test

Step-by-step explanation:

To Find : Which of the following sets is closed under subtraction?

A.) integers,

B.) whole numbers,

C.) natural numbers,

D.) irrational numbers

Solution :

A set of elements is closed under an operation if, when you apply the  operation to elements of the set, you always get another element of  the set.

Natural numbers are only closed under addition and multiplication

Irrational Numbers: This set is closed for none of the operations

Integers: This set is closed only under addition, subtraction, and multiplication.

Whole Numbers: This set is closed only under addition and multiplication.

Option A integers

If we subtract any two integers we will get an integer

eg : -6-8= -14

Thus option A is closed under subtraction

$7 + $0.20p = $5 + $0.30p

Step-by-step explanation:

UPS charges $7 for the first pound and $0.20 for each additional pound.

FedEx charges $5 for the first pound and $0.30 for each additional pound.

Let's take the number of  additional pounds that will make UPS and FedEx cost the same to be p.

$7 + $0.20p = $5 + $0.30p

$7 - $5 = $0.30p - $0.20p

$2 = $0.10p

p = = 20 additional pounds