Finding the Fourth Proportional to 98,569.56, 136,025.86 and 56,128.09

Step by Step Solution

1. Step 1: Write the proportion equation
   98,569.56 : 136,025.86 = 56,128.09 : x
2. Step 2: Convert to fraction form
   98,569.56/136,025.86 = 56,128.09/x
3. Step 3: Cross multiply
   98,569.56x = 136,025.86 × 56,128.09
4. Step 4: Simplify right side
   98,569.56x = 7,634,871,434.45
5. Step 5: Solve for x
   x = 7,634,871,434.45/98,569.56
6. Step 6: Final answer
   x = 77,456.69