Finding the Fourth Proportional to 99,433.57, 137,216.88 and 54,721.57

Step by Step Solution

1. Step 1: Write the proportion equation
   99,433.57 : 137,216.88 = 54,721.57 : x
2. Step 2: Convert to fraction form
   99,433.57/137,216.88 = 54,721.57/x
3. Step 3: Cross multiply
   99,433.57x = 137,216.88 × 54,721.57
4. Step 4: Simplify right side
   99,433.57x = 7,508,723,104.10
5. Step 5: Solve for x
   x = 7,508,723,104.10/99,433.57
6. Step 6: Final answer
   x = 75,514.97