Pre-algebra

Evaluating the expression requires expanding the factorials, which simplifies to 8 times 7 after canceling out the common 6 factorials, resulting in 56. Option A is incorrect because you cannot simply divide the bases to get 8 divided by 6, or 1.33, nor can you subtract them to get 2.

Option B is correct because 25% represents one-quarter of a whole, and dividing 80 by 4 yields 20. Option C is a common trap because students might confuse the percentage rate of 25% with the actual calculated value. Option A is incorrect because 15 is only 18.75% of 80.

Option B is correct because 25% represents one-quarter of a whole, and dividing 80 by 4 yields 20. A diagram for this topic isn't available yet — the worked example below walks the same reasoning step by step.

• !Option C is a common trap because students might confuse the percentage rate of 25% with the actual calculated value.
• !Evaluating the expression requires expanding the factorials, which simplifies to 8 times 7 after canceling out the common 6 factorials, resulting in 56.

Answer each from memory — you'll see instantly whether you're right and why.

Run a focused 10-question mini-mock on Pre-algebra and see it stick.