Finding the Fourth Proportional to 9,861.42, 13,608.36 and 5,385

Step by Step Solution

1. Step 1: Write the proportion equation
   9,861.42 : 13,608.36 = 5,385 : x
2. Step 2: Convert to fraction form
   9,861.42/13,608.36 = 5,385/x
3. Step 3: Cross multiply
   9,861.42x = 13,608.36 × 5,385
4. Step 4: Simplify right side
   9,861.42x = 73,281,018.60
5. Step 5: Solve for x
   x = 73,281,018.60/9,861.42
6. Step 6: Final answer
   x = 7,431.08