Percent of Change Practice — Increase & Decrease (Free)

Practice percent of increase and decrease with this free tool. It gives you an old and a new value, checks your percent answer instantly, and shows how to find the change and convert it to a percent.

How the practice works

1. Pick a difficulty.
2. Find the percent of change and press Check.
3. See the feedback and step-by-step solution, then press Next.

The formula

Percent of change = (new − old) / old × 100%. A positive result is an increase; a negative result is a decrease. The solution panel shows the change, the division, and the conversion to a percent.

Frequently asked questions

What is an example of percent of change?

If a plant grows from 40 cm to 50 cm, the change is 50 − 40 = 10 cm. Divide by the original value: 10 ÷ 40 = 0.25. Multiply by 100 to get a 25% increase. The key is always dividing by the old value, not the new one. The practice tool shows this same change, division and conversion for every problem.

How do you solve percent of change problems?

Use percent of change = (new − old) ÷ old × 100%. A positive answer is an increase and a negative answer is a decrease. If a jacket drops from $80 to $60, the change is −20, and −20 ÷ 80 = −0.25, so it is a 25% decrease. Write the old and new values clearly before you start so you do not swap them.

What do percentage change questions look like?

Most give an old value and a new value and ask for the percent increase or decrease. For example, a ticket price rises from $25 to $30: the change is 5, and 5 ÷ 25 = 0.2, a 20% increase. A common error is dividing by the new price, which gives about 16.7%. Others ask you to work backward from a percent to find the new value.

Is there a percent of change practice worksheet?

You can make your own from the free practice tool. Copy several generated problems onto paper, solve each with the formula, and label your answer as an increase or a decrease. Then enter your answers to check them and read the step-by-step solutions. Redo any problem you miss, paying attention to whether you divided by the original value.

Where can I find percent of change practice problems?

The percent of change practice tool generates unlimited increase and decrease problems at several difficulty levels. Each one gives an old and a new value, checks your percent, and checks the direction of the change too. Start on the easier level with round numbers, like 50 to 75 (a 50% increase), then move up once you are getting them right consistently.

Read the full lesson: learn the method step by step.

How to use Percent of Change Practice, Increase & Decrease as real practice

Percent of Change Practice, Increase & Decrease works best when it is used as a short, focused study session rather than a quick click-through activity. The goal is not simply to finish the problems. The goal is to notice which skills feel automatic, which skills still need review, and which mistakes happen when you rush.

Start with a clean piece of scratch paper. For each item, solve each item on paper first, then use the page to check your answer and study the explanation. If you get something wrong, do not immediately move on. Write the correct step, circle the part that caused the mistake, and try one similar item before continuing. That small correction habit is what turns an online practice activity into lasting math improvement.

A three-round study routine

This routine is simple, but it solves a common problem: students often practice only until an answer looks familiar. Real readiness means you can solve a fresh problem without hints, explain the first step, and check whether the final answer is reasonable.

What to write down while you practice

Keep a tiny mistake log next to the activity. You only need three columns: the topic, the mistake, and the correction. For example, a student might write “fractions,” “forgot common denominator,” and “rewrite both fractions before adding.” A log like that is more useful than a long list of scores because it tells you exactly what to review next.

• If the mistake is a fact or formula, review it before the next round.
• If the mistake is a setup error, copy one worked example and label each step.
• If the mistake is from rushing, slow down and require written work for the next five items.
• If the same mistake appears twice, stop and review that topic before continuing.

When you are ready to move on

You are ready for the next topic when you can get several items correct in a row and explain why the method works. A score by itself is helpful, but it is not the whole story. You should also be able to describe the rule, formula, or pattern that the activity is testing.

For test preparation, come back to Percent of Change Practice, Increase & Decrease after a day or two and try a fresh round. If the skill still feels easy after a short break, it is much more likely to stay with you during a quiz, unit test, or standardized test. If it feels shaky, that is useful information too: it tells you exactly where to spend your next study session.

Study tips for parents and teachers

When using this page with a student, ask for the reasoning before the answer. Questions such as “What is the first step?”, “Why did you choose that operation?”, and “How can you check it?” help students build mathematical language. That matters because many test questions measure more than calculation; they also measure whether the student can read the problem, choose a method, and explain a result.

Short sessions are usually best. Ten to fifteen minutes of careful practice can be more productive than a long session full of guessing. End by naming one skill that improved and one skill to review next time. That keeps practice positive, specific, and easy to continue.

Your next practice step

After finishing Percent of Change Practice, Increase & Decrease, choose one next step instead of trying to study everything at once. If the activity felt easy, increase the challenge by working faster, mixing in older topics, or explaining each answer without notes. If it felt difficult, lower the pressure: redo a smaller set, copy one correct example, and focus on accuracy before speed.

A useful rule is to review the same skill three times: once today, once tomorrow, and once later in the week. Spaced review is especially helpful for math because it tells you whether the method truly stuck or only felt familiar right after practice. Use this practice activity as one stop in that review cycle, then return to it when you want to check retention.