Finding the Fourth Proportional to 8,891.31, 12,260.79 and 7,636.50

Step by Step Solution

1. Step 1: Write the proportion equation
   8,891.31 : 12,260.79 = 7,636.50 : x
2. Step 2: Convert to fraction form
   8,891.31/12,260.79 = 7,636.50/x
3. Step 3: Cross multiply
   8,891.31x = 12,260.79 × 7,636.50
4. Step 4: Simplify right side
   8,891.31x = 93,629,522.84
5. Step 5: Solve for x
   x = 93,629,522.84/8,891.31
6. Step 6: Final answer
   x = 10,530.45