Finding the Fourth Proportional to 99,578.70, 137,410.83 and 57,128.22

Step by Step Solution

1. Step 1: Write the proportion equation
   99,578.70 : 137,410.83 = 57,128.22 : x
2. Step 2: Convert to fraction form
   99,578.70/137,410.83 = 57,128.22/x
3. Step 3: Cross multiply
   99,578.70x = 137,410.83 × 57,128.22
4. Step 4: Simplify right side
   99,578.70x = 7,850,036,126.62
5. Step 5: Solve for x
   x = 7,850,036,126.62/99,578.70
6. Step 6: Final answer
   x = 78,832.48