1.15.1 Solving Proportions

Algebra 11.15.1 Solving Proportions

Search for key terms or text.

1.15.1 Solving Proportions

1.15.1 • Solving Proportions

Warm Up

Solve each of the following proportions:

$\frac{x}{56} = \frac{7}{8}$

Compare your answer:


Cross multiply	$8 x = 7 (56)$
Simplify	$8 x = 392$
Divide both sides by 8	$\frac{8 x}{8} = \frac{392}{8}$
Simplify	$x = 49$

This table demonstrates the step-by-step process for solving an algebraic equation using cross multiplication.

$\frac{56}{72} = \frac{y}{9}$

Compare your answer:


Cross multiply	$56 (9) = 72 y$
Simplify	$504 = 72 y$
Divide both sides by 72	$\frac{504}{72} = \frac{72 y}{72}$
Simplify	$x = 7$

Step-by-step solution of a mathematical equation.

$\frac{98}{154} = \frac{- 7}{p}$

Compare your answer:


Cross multiply	$98 p = - 7 (154)$
Simplify	$98 p = - 1078$
Divide both sides by 98	$\frac{98 p}{98} = \frac{- 1078}{98}$
Simplify	$p = - 11$

This table illustrates the step-by-step solution process for an algebraic equation to find the value of 'p'.

Previous Next

Order a print copy

Citation/Attribution

This book may not be used in the training of large language models or otherwise be ingested into large language models or generative AI offerings without OpenStax's permission.

Want to cite, share, or modify this book? This book uses the Creative Commons Attribution-NonCommercial-ShareAlike License and you must attribute OpenStax.

Attribution information

If you are redistributing all or part of this book in a print format, then you must include on every physical page the following attribution:
Access for free at https://openstax.org/books/algebra-1/pages/about-this-course
If you are redistributing all or part of this book in a digital format, then you must include on every digital page view the following attribution:
Access for free at https://openstax.org/books/algebra-1/pages/about-this-course

Citation information

Use the information below to generate a citation. We recommend using a citation tool such as this one.
- Authors: Lynn Marecek, MaryAnne Anthony-Smith, Andrea Honeycutt Mathis, Jay Abramson, Sharon North, Amy Baldwin, Alyssa Howell
- Publisher/website: OpenStax
- Book title: Algebra 1
- Publication date: Jun 4, 2025
- Location: Houston, Texas
- Book URL: https://openstax.org/books/algebra-1/pages/about-this-course
- Section URL: https://openstax.org/books/algebra-1/pages/1-15-1-solving-proportions

© Jan 20, 2026 OpenStax. Textbook content produced by OpenStax is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike License . The OpenStax name, OpenStax logo, OpenStax book covers, OpenStax CNX name, and OpenStax CNX logo are not subject to the Creative Commons license and may not be reproduced without the prior and express written consent of Rice University.