Finding the Fourth Proportional to 156,128.20, 215,399.28 and 102,443.04

Step by Step Solution

1. Step 1: Write the proportion equation
   156,128.20 : 215,399.28 = 102,443.04 : x
2. Step 2: Convert to fraction form
   156,128.20/215,399.28 = 102,443.04/x
3. Step 3: Cross multiply
   156,128.20x = 215,399.28 × 102,443.04
4. Step 4: Simplify right side
   156,128.20x = 22,066,157,057.01
5. Step 5: Solve for x
   x = 22,066,157,057.01/156,128.20
6. Step 6: Final answer
   x = 141,333.58