Practice Representation in Math

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

Quick Recap

A mathematical representation is any format — diagram, equation, table, graph, or symbolic expression — used to encode and communicate a mathematical idea or relationship between quantities.

The same idea can be shown in multiple ways—each reveals different aspects.

Showing a random 20 of 50 problems.

Example 1

easy
A pie chart and a bar chart show the same survey data. What does this illustrate about representation?

Example 2

medium
A system of two linear equations can be a pair of lines (graph) or a matrix equation Ax=b. Which representation generalizes better to 100 equations, and why?

Example 3

hard
The map f sends 1→a, 2→b, 3→c. Write f as a set of ordered pairs.

Example 4

easy
To show that two angles are equal, which representation usually helps most: a labeled diagram or a paragraph of words?

Example 5

challenge
A graph appears to show f(x)=x2−1x−1 as the line y=x+1. Explain how the graphical representation can mislead, and which representation corrects it.

Example 6

medium
Convert 58 to a percent.

Example 7

challenge
Convert the complex number 1+i from rectangular to polar form.

Example 8

medium
Represent the line y=3x−2 as a y-intercept and slope pair.

Example 9

medium
A motion problem is easier in a position-vs-time graph than in a paragraph. Name the representation switch and the feature it exposes.

Example 10

challenge
Counting lattice paths from (0,0) to (m,n) can be represented as binomial coefficients or as a grid-walk picture. Show both representations give (m+nm) and explain why the symbolic one scales.

Example 11

easy
Write the solution set of x2=9 in (a) roster notation, (b) set-builder notation.

Example 12

medium
Express 'x is at most 3' as an inequality.

Example 13

medium
Convert 720 to a decimal.

Example 14

medium
Convert the recurring decimal 0.3‾ to a fraction.

Example 15

easy
What kind of representation is a Venn diagram?

Example 16

medium
A function doubles its input and adds 1. Write the rule symbolically.

Example 17

medium
Complex number z can be written a+bi or r(cos⁡θ+isin⁡θ). Which representation makes multiplying two complex numbers simplest?

Example 18

hard
Express the parabola y=x2−4x+5 in vertex form.

Example 19

medium
A probability problem is stated in words. Drawing a tree diagram changes the representation. What does the tree make explicit?

Example 20

medium
Which numerical representation makes it easiest to add 14 and 0.5?