Finding the Fourth Proportional to 283,139.72, 390,733.58 and 155,815.31

Step by Step Solution

1. Step 1: Write the proportion equation
   283,139.72 : 390,733.58 = 155,815.31 : x
2. Step 2: Convert to fraction form
   283,139.72/390,733.58 = 155,815.31/x
3. Step 3: Cross multiply
   283,139.72x = 390,733.58 × 155,815.31
4. Step 4: Simplify right side
   283,139.72x = 60,882,274,385.02
5. Step 5: Solve for x
   x = 60,882,274,385.02/283,139.72
6. Step 6: Final answer
   x = 215,025.55