Finding the Fourth Proportional to 99,013.98, 136,648.79 and 56,564.31

Step by Step Solution

1. Step 1: Write the proportion equation
   99,013.98 : 136,648.79 = 56,564.31 : x
2. Step 2: Convert to fraction form
   99,013.98/136,648.79 = 56,564.31/x
3. Step 3: Cross multiply
   99,013.98x = 136,648.79 × 56,564.31
4. Step 4: Simplify right side
   99,013.98x = 7,729,444,518.68
5. Step 5: Solve for x
   x = 7,729,444,518.68/99,013.98
6. Step 6: Final answer
   x = 78,064.17