Finding the Fourth Proportional to 72,045.54, 99,424.35 and 39,780.05

Step by Step Solution

1. Step 1: Write the proportion equation
   72,045.54 : 99,424.35 = 39,780.05 : x
2. Step 2: Convert to fraction form
   72,045.54/99,424.35 = 39,780.05/x
3. Step 3: Cross multiply
   72,045.54x = 99,424.35 × 39,780.05
4. Step 4: Simplify right side
   72,045.54x = 3,955,105,117.10
5. Step 5: Solve for x
   x = 3,955,105,117.10/72,045.54
6. Step 6: Final answer
   x = 54,897.29