if I bought an 8 foot piece of lumber to trim out a bookcase. Altogether I need 100 inches of lumber to trim. Do I have enough?

8 * 12 = ?

No

To calculate whether you have enough lumber, you need to compare the length of the lumber you bought (8 feet) with the length you require (100 inches).

First, let's convert the length of the lumber you bought to inches. Since 1 foot is equal to 12 inches, an 8-foot piece of lumber would be 8 * 12 = 96 inches long.

Now, we can compare the length you require (100 inches) with the length of the lumber you have (96 inches).

Since 96 inches is less than 100 inches, you do not have enough lumber to trim out the bookcase. You would need to purchase additional lumber to meet the required length.