Sam is comparing the half-life of two isotopes of uranium. The half-life of Uranium-238 is 4.5×109

Question

4.5
×
10
9
years. The half-life of Uranium-233 is 1.6×105
1.6
×
10
5
years. He computed how much greater the half-life of Uranium-238 is than that of Uranium-233, and his calculator displayed the number 2.81E4. What is this number in scientific notation?

Answer 1

The number displayed by Sam's calculator, 2.81E4, is already in scientific notation. The format "E4" indicates that the decimal should be moved 4 places to the right. Therefore, 2.81E4 in standard form is:

\[ 2.81 \times 10^4 = 28100 \]

In scientific notation, it remains \( 2.81 \times 10^4 \).