Hello kids! Today we'll learn about counting. When we have just a few things like apples, we can count them one by one. But what happens when we have many, many things? It gets confusing! That's why we need smart counting methods to help us.
Now let's learn the Addition Principle! When we choose EITHER this OR that, we add the numbers together. Look at these snacks - we can choose either 3 apples OR 4 oranges. Since we pick one type, we add: 3 plus 4 equals 7 total choices! Here's another example with shirts - 2 red shirts OR 3 blue shirts gives us 5 total choices. Remember: OR means ADD!
Great! Now let's practice the addition principle with more examples. Remember to look for the word OR - that's our clue to add! First example: 2 indoor games OR 3 outdoor games equals 5 total games. Next: 4 story books OR 2 picture books equals 6 books. Finally: 3 crayons OR 2 markers equals 5 art supplies. See the pattern? When you choose between different groups, you add them up!
Now let's learn the Multiplication Principle! When we choose this AND that, we multiply the numbers. Look at these clothes - we need to pick 2 shirts AND 3 pants. Each shirt can go with each pair of pants, giving us 2 times 3 equals 6 different outfits! Here's another example: 3 main foods AND 2 drinks makes 3 times 2 equals 6 different meals. Remember: AND means MULTIPLY!
Great job learning both principles! Let's review: OR means ADD, AND means MULTIPLY. Here are some practice problems. Ice cream with 3 flavors AND 2 toppings gives us 3 times 2 equals 6 combinations. Building blocks with 2 colors AND 4 shapes makes 2 times 4 equals 8 different blocks. Planning activities with 2 morning AND 3 afternoon choices gives 2 times 3 equals 6 daily plans. Remember: if you're choosing between things, add them. If you're combining things together, multiply them!