Finding the Fourth Proportional to 8,999.58, 12,418.83 and 5,642.25

Step by Step Solution

1. Step 1: Write the proportion equation
   8,999.58 : 12,418.83 = 5,642.25 : x
2. Step 2: Convert to fraction form
   8,999.58/12,418.83 = 5,642.25/x
3. Step 3: Cross multiply
   8,999.58x = 12,418.83 × 5,642.25
4. Step 4: Simplify right side
   8,999.58x = 70,070,143.57
5. Step 5: Solve for x
   x = 70,070,143.57/8,999.58
6. Step 6: Final answer
   x = 7,785.93