# Using and in Boolean if Statements

**00:00**
In this lesson and the next, you’ll see some typical Boolean contexts where an `and`

operator might be used. Boolean contexts typically appear as the conditions in `if`

and `while`

statements.

**00:15**
These instructions modify the flow of execution in your program, either selecting one section of code or another to be executed or selecting a section of code to be repeated.

**00:26**
You can create more effective conditions to direct the flow of your program through the use of expressions which use the `and`

operation.

**00:36**
Let’s first see an example using the `if`

statement. Here is a simple segment of code that describes a person based on his or her age, following an input statement, which will allow us to test it.

**00:50**
To be classified as an adult in this example means to be older than eighteen and up to and including sixty-five. So you need to combine two inequalities, `age`

is greater than `18`

and `age`

is less than or equal to `65`

, with the operation `and`

to indicate that an age must meet both conditions to be considered an adult.

**01:13**
And you can see other classifications use `and`

to connect inequalities that give lower and upper limits on `age`

to be in that category.

**01:23**
So in the terminal, you can run this a few times to see each branch being selected.

**01:33**
Here, `15`

is greater than or equal to `0`

, but it’s not less than or equal to `9`

. So the first condition is false. So the program drops to the next condition.

**01:46**
`15`

is greater than `9`

, and `15`

is also less than or equal to `18`

. Since both these conditions are true, the `and`

of them is `True`

, and the program executes the then code for this conditional, telling us you’re an adolescent.

**02:05**
If you try a younger age, here, both of the expressions in the first condition are true: `age`

is greater than or equal to `0`

and less than or equal to `9`

.

**02:16**
So the entire condition is true, so the child phrase should be output. If you continue this, you can find ages that fit the other two conditions as well.

**02:29**
`30`

is greater than `18`

and less than or equal to `65`

, putting us in the adult category.

**02:41**
And `70`

makes at least one expression fail in each of the first three conditions. It’s not less than or equal to `9`

, not less than or equal to `18`

, not less than or equal to `65`

.

**02:53**
So it’s not until the last expression, `> 65`

, that we get a true condition.

**03:05**
In the next lesson, you’ll see expressions using `and`

in `while`

loops.

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