To determine the opposite number of β78β, we need to understand what the opposite of a number means in mathematics.
The opposite of a number is simply a number with the same magnitude but the opposite sign. For any real number a, its opposite is βa. When a is already negative, its opposite is positive.
Given the number β78β, we will apply the following steps:
- Identify the sign and magnitude: The given number is β78β, a negative fraction.
- Apply sign change: The opposite is simply the positive version of β78β, which is 78β.
Thus, the opposite of β78β is 78β.
Therefore, the correct answer is 78β.