A specific quantity means that you are talking about how much of something there is. It's like when you count the number of toys you have or how many apples are in the fruit bowl. It's important to be specific about the quantity so you know exactly how much you have.
Imagine you have a jar of marbles. You can count how many marbles are in the jar by grouping them in sets of ten. If you count five sets of ten marbles, you can say you have 50 marbles. That's a specific quantity!
When you go to the store with your parents, they might ask you to help them find a specific quantity of something. For example, they might ask you to get six apples. This means you need to find exactly six apples, not more or less.
Having a specific quantity helps you stay organized and keep track of things. So always remember to count and be specific!