What is the method to convert a fraction or decimal into a percent?

To convert a fraction or a decimal into a percent, the correct method involves multiplying the value by 100. This is because a percent represents a value out of 100. When you multiply a decimal or fraction by 100, you shift the decimal point two places to the right, effectively converting it into a percentage.

For instance, if you have a decimal like 0.75, multiplying it by 100 results in 75, which means 0.75 is equivalent to 75%. Similarly, if you had a fraction such as 1/4, converting it to a decimal gives you 0.25. When you multiply 0.25 by 100, you'll arrive at 25%, indicating that 1/4 is equivalent to 25%.

This method is straightforward and efficient, allowing for an easy conversion of any decimal or fraction into percent format, making option C the right approach for this question.