Finding the Fourth Proportional to 209,435.27, 311,783.99 and 208,189.69

Step by Step Solution

1. Step 1: Write the proportion equation
   209,435.27 : 311,783.99 = 208,189.69 : x
2. Step 2: Convert to fraction form
   209,435.27/311,783.99 = 208,189.69/x
3. Step 3: Cross multiply
   209,435.27x = 311,783.99 × 208,189.69
4. Step 4: Simplify right side
   209,435.27x = 64,910,210,404.65
5. Step 5: Solve for x
   x = 64,910,210,404.65/209,435.27
6. Step 6: Final answer
   x = 309,929.71