Finding the Fourth Proportional to 72,309.62, 99,789.36 and 40,478.34

Step by Step Solution

1. Step 1: Write the proportion equation
   72,309.62 : 99,789.36 = 40,478.34 : x
2. Step 2: Convert to fraction form
   72,309.62/99,789.36 = 40,478.34/x
3. Step 3: Cross multiply
   72,309.62x = 99,789.36 × 40,478.34
4. Step 4: Simplify right side
   72,309.62x = 4,039,307,642.46
5. Step 5: Solve for x
   x = 4,039,307,642.46/72,309.62
6. Step 6: Final answer
   x = 55,861.28