1. Move the decimal point:

* Start with 64120. Since there's no decimal point shown, it's understood to be at the very end: 64120.

* Move the decimal point to the left until you have a number between 1 and 10. In this case, you'll move it four places to the left: 6.4120

2. Determine the exponent:

* You moved the decimal point four places to the left, so the exponent of 10 will be +4.

3. Write the final answer:

* 6.4120 x 10⁴

Therefore, 64120 in scientific notation is 6.4120 x 10⁴.