Question

Write statements using combined assignment operators to perform the following: a) Add 6 to \(x\) b) Subtract 4 from amount c) Multiply \(y\) by 4 d) Divide total by 27 c) Store in \(x\) the remainder of \(x\) divided by 7

Short answer

Question: Write the statements using combined assignment operators to perform the following tasks: a) Add 6 to \(x\) b) Subtract 4 from `amount` c) Multiply \(y\) by 4 d) Divide `total` by 27 e) Store in \(x\) the remainder of \(x\) divided by 7 Answer: a) `x += 6` b) `amount -= 4` c) `y *= 4` d) `total /= 27` e) `x %= 7`

Step-by-step solution

Use the '+=' operator

To add 6 to \(x\), we can use the '+=' operator. This operator adds the value on the right to the variable on the left and stores the result back into the variable on the left. ```python x += 6 ``` #b) Subtract 4 from amount#

Use the '-=' operator

To subtract 4 from `amount`, we can use the '-=' operator. Like the '+=' operator, this operator subtracts the value on the right from the variable on the left and stores the result back into the variable on the left. ```python amount -= 4 ``` #c) Multiply \(y\) by 4#

Use the '*=' operator

To multiply \(y\) by 4, we can use the '*=' operator. This operator multiplies the variable on the left by the value on the right and stores the result back into the variable on the left. ```python y *= 4 ``` #d) Divide total by 27#

Use the '/=' operator

To divide `total` by 27, we can use the '/=' operator. This operator divides the variable on the left by the value on the right and stores the result back into the variable on the left. ```python total /= 27 ``` #c) Store in \(x\) the remainder of \(x\) divided by 7#

Use the '%=' operator

To store in \(x\) the remainder of \(x\) divided by 7, we can use the '%=' operator. This operator calculates the remainder when the variable on the left is divided by the value on the right and stores the result back into the variable on the left. ```python x %= 7 ```

Key concepts

+= operator

The += operator in programming is known as an assignment operator that performs addition and assignment in one step. Instead of writing x = x + 6, we simplify the expression with x += 6. This operator is invaluable for modifying the value of a variable without needing to reference the variable twice.

Consider you have x = 5. Applying x += 6 will update x to 11. This succinct syntax is not only cleaner but also reduces the potential for errors when updating variables. It's widely used in loops and operations where a variable needs to be updated iteratively.

-= operator

Similarly, the -= operator is a shortcut for subtraction and reassignment. It subtracts a number from a variable and immediately updates that variable with the new value. Instead of amount = amount - 4, you can write amount -= 4.

If you start with amount = 10, after amount -= 4, the amount would be 6. This operator is particularly handy for coding situations involving decrementing values, such as counting down or reducing a total by a certain amount in each step of a process.

*= operator

Moving on to multiplication, the *= operator multiplies a variable by the value on its right and then assigns the result back to the variable. So, in the case of y *= 4, if y originally held the value 3, after this operation, it would hold the value 12.

This operator enables concise and clear code when scaling a value by a factor, which is a common occurrence in mathematical calculations, games programming, and algorithm development.

/= operator

The /= operator simplifies the division and assignment process by performing both actions simultaneously. If we have total /= 27, it divides the current value of total by 27 and assigns the quotient back to total.

This operator is a timesaver during tasks that require dividing a variable repeatedly by a number, such as normalizing values or creating averages.

%= operator

Lastly, the %= operator is used for modulo division—which means it finds the remainder after division—and assigns it back to the variable. The statement x %= 7 takes the current value of x, divides it by 7, and then updates x to the remainder from that division.

The %= operator is useful in cases where you need to enforce limits (like wrapping numbers around in a circular range) or determining if a number is divisible by another (no remainder equals divisibility). It's a staple in algorithms that need to deal with cyclical values or intervals.