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 β€” diagram, equation, table, graph, or symbolic expression β€” used to encode and communicate a mathematical idea or relationship between quantities.

The same idea can be shown in multiple waysβ€”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=bA\mathbf{x}=\mathbf{b}. Which representation generalizes better to 100100 equations, and why?

Example 3

hard
The map ff sends 1β†’a1 \to a, 2β†’b2 \to b, 3β†’c3 \to c. Write ff 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)=x2βˆ’1xβˆ’1f(x)=\frac{x^2-1}{x-1} as the line y=x+1y=x+1. Explain how the graphical representation can mislead, and which representation corrects it.

Example 6

medium
Convert 58\frac{5}{8} to a percent.

Example 7

challenge
Convert the complex number 1+i1+i from rectangular to polar form.

Example 8

medium
Represent the line y=3xβˆ’2y=3x-2 as a yy-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)(0,0) to (m,n)(m,n) can be represented as binomial coefficients or as a grid-walk picture. Show both representations give (m+nm)\binom{m+n}{m} and explain why the symbolic one scales.

Example 11

easy
Write the solution set of x2=9x^2 = 9 in (a) roster notation, (b) set-builder notation.

Example 12

medium
Express 'xx is at most 33' as an inequality.

Example 13

medium
Convert 720\tfrac{7}{20} to a decimal.

Example 14

medium
Convert the recurring decimal 0.3β€Ύ0.\overline{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 11. Write the rule symbolically.

Example 17

medium
Complex number zz can be written a+bia+bi or r(cos⁑θ+isin⁑θ)r(\cos\theta + i\sin\theta). Which representation makes multiplying two complex numbers simplest?

Example 18

hard
Express the parabola y=x2βˆ’4x+5y=x^2-4x+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\tfrac{1}{4} and 0.50.5?