What’s the answer to this equation?

Simplify (a/b - b/a) times (a - a^2/a+b) a - a^2/a=b is a mixed number

Find the number of positive three-digit even integers whose digits are among 9, 8, 7,5, 3, and 1.

Sheila wants to bake six muffins but the recipe is for 12 muffins . this means you only need half of the ingredients listed how much of the of each ingredient does she need? one cup and banana chips ,7 tablespoons oil , two eggs, 3/4 cups flour 1/4 cup walnuts show all you work and justify your answer using a baby toulmin.