Use scientific notation to determine which of these numbers is least: 123,893, 31,892 or 12,786. Write your answer in scientific notation, expressed to the exact decimal place.
To determine which of these numbers is least, we need to express them in scientific notation and compare their exponents.
Let's start with 123,893. We can express this number in scientific notation as 1.23893 x 10^5.
Next, let's express 31,892 in scientific notation. It would be 3.1892 x 10^4.
Finally, let's express 12,786 in scientific notation. It would be 1.2786 x 10^4.
Comparing the exponents, we can see that 1.2786 x 10^4 is the least.