Finding the Fourth Proportional to 209,436.27, 311,785.47 and 208,190.69

Step by Step Solution

1. Step 1: Write the proportion equation
   209,436.27 : 311,785.47 = 208,190.69 : x
2. Step 2: Convert to fraction form
   209,436.27/311,785.47 = 208,190.69/x
3. Step 3: Cross multiply
   209,436.27x = 311,785.47 × 208,190.69
4. Step 4: Simplify right side
   209,436.27x = 64,910,832,131.27
5. Step 5: Solve for x
   x = 64,910,832,131.27/209,436.27
6. Step 6: Final answer
   x = 309,931.19