Finding the Fourth Proportional to 9,861.50, 13,609.06 and 5,385.64

Step by Step Solution

1. Step 1: Write the proportion equation
   9,861.50 : 13,609.06 = 5,385.64 : x
2. Step 2: Convert to fraction form
   9,861.50/13,609.06 = 5,385.64/x
3. Step 3: Cross multiply
   9,861.50x = 13,609.06 × 5,385.64
4. Step 4: Simplify right side
   9,861.50x = 73,293,506.22
5. Step 5: Solve for x
   x = 73,293,506.22/9,861.50
6. Step 6: Final answer
   x = 7,432.29