Practice Subset in Math

Use these practice problems to test your method after reviewing the concept explanation and worked examples.

Quick Recap

Set AA is a subset of set BB if every element of AA is also an element of BB, written AβŠ†BA \subseteq B.

Every single thing in AA can also be found inside BB. Think of AA as fitting entirely within BB, like a small circle inside a big one.

Showing a random 20 of 50 problems.

Example 1

easy
Is {5}βŠ†{1,5,9}\{5\} \subseteq \{1, 5, 9\}?

Example 2

hard
How many subsets of {1,2,3,4,5}\{1, 2, 3, 4, 5\} have size exactly 33?

Example 3

easy
Let A={1,2,3,4,5}A = \{1, 2, 3, 4, 5\} and B={2,4}B = \{2, 4\}. Determine whether BβŠ†AB \subseteq A.

Example 4

easy
Let A={1,3}A = \{1, 3\} and B={1,2,3,4}B = \{1, 2, 3, 4\}. Is AβŠ†BA \subseteq B? Is BβŠ†AB \subseteq A?

Example 5

challenge
If AβŠ†BA \subseteq B, prove that ∣Aβˆ£β‰€βˆ£B∣|A| \le |B| for finite sets.

Example 6

medium
List all subsets of S={a,b,c}S = \{a, b, c\}.

Example 7

medium
Is NβŠ†Z\mathbb{N} \subseteq \mathbb{Z}? Is ZβŠ†N\mathbb{Z} \subseteq \mathbb{N}?

Example 8

medium
True or false: {1,2}βŠ†{{1,2},3}\{1, 2\} \subseteq \{\{1, 2\}, 3\}.

Example 9

easy
Let X={1,2,3}X = \{1, 2, 3\} and Y={1,2,3,4,5}Y = \{1, 2, 3, 4, 5\}. Is XβŠ†YX \subseteq Y? Is YβŠ†XY \subseteq X?

Example 10

medium
If AβŠ†BA \subseteq B and ∣B∣=5|B| = 5, what is the maximum possible ∣A∣|A|?

Example 11

challenge
Prove that the empty set βˆ…\emptyset is a subset of every set AA.

Example 12

medium
Given A={x:xΒ isΒ even,Β 0<x<10}A = \{x : x \text{ is even, } 0 < x < 10\} and B={2,4,6,8}B = \{2, 4, 6, 8\}, is A=BA = B?

Example 13

medium
Given A={1,2}A = \{1, 2\}, is {1,2}∈\{1, 2\} \in the power set of AA, and is {1,2}βŠ†A\{1, 2\} \subseteq A?

Example 14

medium
How many subsets does {1,2,3}\{1, 2, 3\} have?

Example 15

medium
How many subsets of {1,2,3,4}\{1, 2, 3, 4\} are there?

Example 16

hard
How many subsets of {1,2,…,10}\{1, 2, \dots, 10\} contain at least one odd number?

Example 17

easy
Is A={1,2}A = \{1, 2\} a subset of B={1,2,3}B = \{1, 2, 3\}?

Example 18

medium
List all subsets of {1,2}\{1, 2\} that contain 11.

Example 19

easy
Is A={1,2,3}A = \{1, 2, 3\} a subset of itself?

Example 20

easy
Is the set of even integers a subset of the set of integers?