To add or subtract terms with exponents, both the base and the exponent must be the same. In this case they are so subtract the coefficients and retain the base and exponent:

8b⁶ - 4b⁶
(8 - 4)b⁶
4b⁶

A ratio of 4:1 means that there are 4 home fans for every one visiting fan. So, of every 5 fans, 4 are home fans and \( \frac{4}{5} \) of every fan in the stadium is a home fan:

41,000 fans x \( \frac{4}{5} \) = \( \frac{164000}{5} \) = 32,800 fans.

To subtract these radicals together their radicands must be the same:

3\( \sqrt{12} \) - 5\( \sqrt{3} \)
3\( \sqrt{4 \times 3} \) - 5\( \sqrt{3} \)
3\( \sqrt{2^2 \times 3} \) - 5\( \sqrt{3} \)
(3)(2)\( \sqrt{3} \) - 5\( \sqrt{3} \)
6\( \sqrt{3} \) - 5\( \sqrt{3} \)

Now that the radicands are identical, you can subtract them:

In order to find how many additional workers are needed to staff the extra crews you first need to calculate how many workers are on a crew. There are 20 workers at the company now and that's enough to staff 5 crews so there are \( \frac{20}{5} \) = 4 workers on a crew. 9 crews are needed for the busy season which, at 4 workers per crew, means that the roofing company will need 9 x 4 = 36 total workers to staff the crews during the busy season. The company already employs 20 workers so they need to add 36 - 20 = 16 new staff for the busy season.

There are 4 5-passenger taxis available so that's 4 x 5 = 20 total seats. There are 25 people needing transportation leaving 25 - 20 = 5 who will have to find other transportation.