A clear and detailed step-by-step explanation on how to convert the decimal -0.21 to a fraction, suitable for 18-year-old students.
To convert the decimal -0.21 into a fraction, follow these steps:
0.21 = 21/100
-0.21 = -21/100
-21/100
In conclusion, -0.21 can be expressed as the fraction -21/100.