Final answer:
The decimal equivalent of -9/10 is -0.9, and for -1/3, it is approximately -0.3333.... The conversion involves dividing the numerator by the denominator.
Step-by-step explanation:
The decimal equivalent of the negative fraction -9/10 is simply -0.9. Converting a fraction to a decimal requires division of the numerator by the denominator. Here, dividing -9 by 10 gives us -0.9, which corresponds to option A) -0.9.
For the second fraction, -1/3, dividing -1 by 3 gives us approximately -0.3333..., which is a repeating decimal. The decimal can be rounded to a specific number of decimal places depending on the required precision. However, it is not one of the options provided for the first fraction.