Good job! And yes, it's VERY handy to know about how much you have on hand, in terms of what it will make in "finished food" terms.

One thing... that's why commercial bakers or even serious cooks WEIGHT their flour, sugar, etc (but especially flour) when making bread, cakes, etc. Because 1 cup of flour may weigh up to 20% more or less depending on the humidity at the time. So 1 cup of "damp" flour will work differently than 1 cup of "dry" (light) flour in a bread recipe.

Recipes make up for that by saying "4-5 cups of flour" and then "add flour until dough is workable or no longer sticks to the side of the pan". But most commercial bakers don't have time to fiddle with that... they need to dump in the right amount of flour every time. Hence... they weigh it. And all their recipes are in pounds and ounces (or kilos and grams)...

Summerthyme