Finding the Fourth Proportional to 99,449.06, 137,243.07 and 54,128.69

Step by Step Solution

1. Step 1: Write the proportion equation
   99,449.06 : 137,243.07 = 54,128.69 : x
2. Step 2: Convert to fraction form
   99,449.06/137,243.07 = 54,128.69/x
3. Step 3: Cross multiply
   99,449.06x = 137,243.07 × 54,128.69
4. Step 4: Simplify right side
   99,449.06x = 7,428,787,419.12
5. Step 5: Solve for x
   x = 7,428,787,419.12/99,449.06
6. Step 6: Final answer
   x = 74,699.43