Finding the Fourth Proportional to 156,128.36, 215,449 and 91,588.62

Step by Step Solution

1. Step 1: Write the proportion equation
   156,128.36 : 215,449 = 91,588.62 : x
2. Step 2: Convert to fraction form
   156,128.36/215,449 = 91,588.62/x
3. Step 3: Cross multiply
   156,128.36x = 215,449 × 91,588.62
4. Step 4: Simplify right side
   156,128.36x = 19,732,676,590.38
5. Step 5: Solve for x
   x = 19,732,676,590.38/156,128.36
6. Step 6: Final answer
   x = 126,387.52