Upper and lower bounds
Imagine you have a bunch of toys, and your mom says you can only pick two toys to bring with you to the playground. She also tells you that one toy has to be blue, and the other toy has to be round. Your choices are limited by those rules, so you can't pick any toy you want.
In math, we also have rules that limit what numbers we can use. Upper and lower bounds are like those rules that tell us what numbers we can or can't use. The upper bound is like the highest number you can pick, and the lower bound is like the lowest number you can pick.
For example, let's say you have a number line that goes from 0 to 10. If someone gives you a rule saying "Pick a number between 3 and 7," that means your lower bound is 3, and your upper bound is 7. You can't pick any number below 3 or above 7.
In other words, the bounds are like a fence that keeps the numbers you can use inside a specific area. Just like you can't bring any toy you want to the playground, you can't use any number you want in certain math problems. The upper and lower bounds help you know what numbers are allowed.
In math, we also have rules that limit what numbers we can use. Upper and lower bounds are like those rules that tell us what numbers we can or can't use. The upper bound is like the highest number you can pick, and the lower bound is like the lowest number you can pick.
For example, let's say you have a number line that goes from 0 to 10. If someone gives you a rule saying "Pick a number between 3 and 7," that means your lower bound is 3, and your upper bound is 7. You can't pick any number below 3 or above 7.
In other words, the bounds are like a fence that keeps the numbers you can use inside a specific area. Just like you can't bring any toy you want to the playground, you can't use any number you want in certain math problems. The upper and lower bounds help you know what numbers are allowed.
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