Problem 74 - Algebra 1: Concepts and Skills

Question

Write the decimal as a percent. $$ 0.15 $$

Step-by-Step Solution

Answer

The decimal 0.15 as a percent is 15%.

Step 1: Identify the decimal number

Indicate the decimal number that needs to be converted to a percent, which is 0.15 in this case.

Step 2: Convert the decimal into percent

To turn this decimal into a percent it must be multiplied by 100: 0.15 * 100 = 15.

Step 3: Add the percent symbol

Finally, add the percent symbol: 15 becomes 15%.

Key Concepts

Decimal to Percent Conversion

Converting a decimal to a percent is a fundamental skill in math that helps you understand proportions in everyday life. Let's simplify the process by breaking it down.

Firstly, remember that a decimal is just another way to express a fraction or a part of a whole. For instance, 0.15 can also be seen as 15 out of 100.

• Decide on the decimal you want to convert - in our example, it's 0.15.
• Converting a decimal to a percent involves moving it from a base of 1 to a base of 100.

This change of base is crucial as it transitions the number from its decimal form to a percentage, making it easier to compare with other percentages.

Percent Symbol

A percent symbol (%) is an essential part of percentages. Once you've transformed the decimal, this symbol officially designates the number as a percentage.

The symbol itself stands for 'per hundred,' indicating how many parts out of 100 are being discussed. So when you see 15%, it signifies that 15 parts are out of a possible 100.

• It acts as a clarifying mark that shows the context of your number.
• Always remember to add it after calculating the percent.

Without the percent symbol, the number lacks this key context, potentially leading to misunderstandings.

Multiplying by 100

Multiplying by 100 is the critical step in transforming a decimal into a percent. This process effectively shifts the decimal two places to the right, aligning the value with its percentage form.

Here's why: In mathematics, moving the decimal two places to the right reflects multiplying by 100 because 100 has two zeros - emphasizing the hundredths place.

• This is why 0.15 becomes 15 when multiplied by 100.
• The multiplication highlights the conversion between the decimal form and percentage form clearly.

After you perform the multiplication, don't forget to attach the percent symbol to ensure the number is read as a percentage. This step is crucial to complete the conversion process.