Final answer:
To change 2.1 into a percent, multiply it by 100: 2.1 * 100 = 210%.
Step-by-step explanation:
To change a decimal number into a percent, you simply multiply the decimal by 100 and add the percent sign. In this case, to change 2.1 into a percent, you would multiply it by 100: 2.1 * 100 = 210. Therefore, 2.1 is equal to 210%.
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