Finding the Fourth Proportional to 9,865.78, 13,604.68 and 7,737.50

Step by Step Solution

1. Step 1: Write the proportion equation
   9,865.78 : 13,604.68 = 7,737.50 : x
2. Step 2: Convert to fraction form
   9,865.78/13,604.68 = 7,737.50/x
3. Step 3: Cross multiply
   9,865.78x = 13,604.68 × 7,737.50
4. Step 4: Simplify right side
   9,865.78x = 105,266,211.50
5. Step 5: Solve for x
   x = 105,266,211.50/9,865.78
6. Step 6: Final answer
   x = 10,669.83