The thickness of a u. s. penny is 5.98 x 10-2 inch.
what is the height of a stack of 2.5 x 109 pennies?

Step-by-step explanation:

For this exercise you have to remember the Product of powers property, which states that:

Let be "x" the height in inches of a stack of pennies.

You know that the thickness of 1 pennie is , then, you can write the following proportion:

Solve for "x":

To express this height in Scientific notation the decimal point must be after the first digit, so you must move it one place to the left: