Finding the Fourth Proportional to 99,730.72, 137,628.78 and 54,409.72

Step by Step Solution

1. Step 1: Write the proportion equation
   99,730.72 : 137,628.78 = 54,409.72 : x
2. Step 2: Convert to fraction form
   99,730.72/137,628.78 = 54,409.72/x
3. Step 3: Cross multiply
   99,730.72x = 137,628.78 × 54,409.72
4. Step 4: Simplify right side
   99,730.72x = 7,488,343,383.74
5. Step 5: Solve for x
   x = 7,488,343,383.74/99,730.72
6. Step 6: Final answer
   x = 75,085.62