To find the percentage change from 800000 to 450000, we need to first calculate the difference between the two numbers.

**Step 1: Determine the initial value. The initial value refers to the starting point or the original amount. In this case, the initial value is 800,000.**

**Step 2: Determine the final value. The final value refers to the ending point or the new amount. In this case, the final value is 450,000.**

Step 3: Calculate the decrease in value. To find the decrease, subtract the final value from the initial value:

Decrease = Initial Value - Final Value

Decrease = 800,000 - 450,000

**Step 4: Calculate the percent decrease. To calculate the percent decrease, divide the decrease by the initial value and multiply by 100:**

Percent Decrease = (Decrease / Initial Value) * 100

Percent Decrease = (350,000 / 800,000) * 100

**Step 5: Simplify the fraction (if necessary). In this case, the fraction (350,000 / 800,000) cannot be simplified further.**

**Step 6: Calculate the percent. Now, let's calculate the percent decrease using a calculator or by dividing and multiplying: **

Percent Decrease = (0.4375) * 100

Percent Decrease = 43.75%

So, the percent decrease from 800,000 to 450,000 is 43.75%.

It's important to note that the steps provided above can be used as a general approach to solve any percent decrease problem. Just plug in the appropriate values for the initial and final amounts, and follow the steps accordingly.

Let's explore a couple of examples to further solidify our understanding of percent decrease.

**Example 1:**

Suppose the original price of a laptop was $1,200, and it is now on sale for $960. What is the percent decrease in the price?

Step 1: Determine the initial value.

The initial value is $1,200.

Step 2: Determine the final value.

The final value is $960.

Step 3: Calculate the decrease in value.

Decrease = Initial Value - Final Value

Decrease = $1,200 - $960

Decrease = $240

Step 4: Calculate the percent decrease.

Percent Decrease = (Decrease / Initial Value) * 100

Percent Decrease = ($240 / $1,200) * 100

Percent Decrease = 0.2 * 100

Percent Decrease = 20%

Therefore, the percent decrease in the price of the laptop is 20%.

**Example 2:**

Suppose the number of students in a school decreased from 900 to 720. What is the percent decrease in the student population?

**Step 1: Determine the initial value.**

The initial value is 900.

**Step 2: Determine the final value.**

The final value is 720.

**Step 3: Calculate the decrease in value.**

Decrease = Initial Value - Final Value

Decrease = 900 - 720

Decrease = 180

**Step 4: Calculate the percent decrease.**

Percent Decrease = (Decrease / Initial Value) * 100

Percent Decrease = (180 / 900) * 100

Percent Decrease = 0.2 * 100

Percent Decrease = 20%

Therefore, the percent decrease in the student population is 20%.

These examples demonstrate the application of percent decrease in different scenarios. By following the step-by-step approach, you can easily calculate the percent decrease in any given situation.

Percent decrease represents the amount of decrease relative to the original value, expressed as a percentage. It is a valuable tool for analyzing changes and understanding the magnitude of differences between quantities.