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Most programming languages let you chain math operations together, and C# is no exception. The order of operations you were taught in math class applies in C# too.

- Most programming languages let you chain math operations together, and C# is no exception:
`Console.WriteLine(1 + 2 + 3);`

- Order of operations you were taught in math class applies in C# too.

```
Console.WriteLine(1 + 2 * 3);
```

- If you didn't have order of operations, you'd assume that you add
`1`

to`2`

, getting 3, and then multiply`3 * 3`

to get`9`

. But that's not what we get. - Instead we get 7.
- This is because of order of operations. In chained math operations, multiplication and division operations always come first , and addition and subtraction second .
- C# respects this concept by following something called
**operator precedence**. That is, the evaluation of some operators*precedes*the evaluation of some other operators. The multiplication and division operators have higher precedence that addition and subtraction operators. - So that's why when we evaluate
`1 + 2 * 3`

, we get`7`

and not`9`

. The multiplication operator has higher precedence than the addition operator, so we do the multiplication first, giving us`6`

. We then add`1`

and`6`

, giving us 7. - But suppose we wanted to ensure that the addition operation occurs first. If we were working in a math textbook, we'd add parentheses around the operation to indicate it should go first, no matter what:
`(1 + 2) * 3`

. - And that same notation works in C#. C# will always evaluate math operations within parentheses first, before it goes on to evaluate the rest of the expression. So with the parentheses,
`1 + 2`

is evaluated first, giving`3`

, and then that's multiplied by`3`

to give`9`

.

If you're not comfortable with operator precedence, or you want to learn more, visit these links.

Most programming languages like you change math operations together and 0:00 C# is no exception. 0:05 The order of operations that you were taught in math class supplies in C# too. 0:07 If you didn't have order of operations you'd 0:12 assume that you add 1 to 2 getting 3. 0:15 And then multiply 3 by 3 to get 9, but that's not what we get. 0:17 Instead, the result is 7. 0:24 This is because of order of operations. 0:27 In chain math operations, multiplication and 0:31 division operations always come first and addition and subtraction second. 0:34 C# respects this concept by following something called operator precedents. 0:40 That is, 0:45 the evaluation of some operators precedes the evaluation of some other operators. 0:45 The multiplication and division operators have higher precedents than addition and 0:51 subtraction operators. 0:56 So that's why when we evaluate 1 + 2 x 3, we get 7 and not 9. 0:57 The multiplication operator has higher precedence than the addition operator. 1:02 So we do the multiplication first giving us 6, we then add 1 in 6 giving us 7. 1:08 But suppose we wanted to ensure that the addition operation occurs first. 1:15 If we were working in a math textbook we'd add parentheses around the operation to 1:20 indicate it should go first, and the multiplication should happen second. 1:24 And that same notation works in C#, C# will always evaluate math operations 1:28 within parentheses first before it goes on to evaluate the rest of the expression. 1:33 So with the parentheses 1 + 2 is evaluated first giving 3. 1:39 And then that's multiplied by 3 to give 9. 1:45 If you're not comfortable with operator presidence or you want to learn more, 1:48 check the teachers notes for more info. 1:52

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