Finding the Fourth Proportional to 72,312.16, 99,789.74 and 40,043.72

Step by Step Solution

1. Step 1: Write the proportion equation
   72,312.16 : 99,789.74 = 40,043.72 : x
2. Step 2: Convert to fraction form
   72,312.16/99,789.74 = 40,043.72/x
3. Step 3: Cross multiply
   72,312.16x = 99,789.74 × 40,043.72
4. Step 4: Simplify right side
   72,312.16x = 3,995,952,407.43
5. Step 5: Solve for x
   x = 3,995,952,407.43/72,312.16
6. Step 6: Final answer
   x = 55,259.76