Grade 7 · Ratios and Proportional Relationships

CCSS.MATH.CONTENT.7.RP.A.3

Use proportional relationships to solve multistep ratio and percent problems.

Read this standard on the official Common Core site

Lessons that teach this standard

• Discounts, Sales Tax and Tips

  How to work out a sale price, add sales tax, and calculate a tip, using one multiplication instead of two steps — and why the order does not matter.

• What Percent Is One Number of Another?

  How to find what percent one number is of another: divide the part by the whole and multiply by 100, and how to tell which number is the whole.

• Percent Increase and Decrease

  How to find a percent increase or decrease, why the change is always measured against the original, and how to apply one in a single multiplication.

• How to Find a Percent of a Number

  Three ways to find a percent of a number: convert to a decimal and multiply, use a fraction, or build it from 10% and 1% in your head.

• Percent Word Problems: Which of the Three Questions Is It?

  Every percent word problem is one of three questions. How to tell which you have been asked, and how to solve each one, with worked examples.

• Simple Interest: The Formula and What Each Letter Means

  How to use I = Prt to find simple interest, how to rearrange it for any missing letter, and why simple interest differs from compound interest.