Finding the Fourth Proportional to 9,856.87, 13,602.81 and 5,380.89

Step by Step Solution

1. Step 1: Write the proportion equation
   9,856.87 : 13,602.81 = 5,380.89 : x
2. Step 2: Convert to fraction form
   9,856.87/13,602.81 = 5,380.89/x
3. Step 3: Cross multiply
   9,856.87x = 13,602.81 × 5,380.89
4. Step 4: Simplify right side
   9,856.87x = 73,195,224.30
5. Step 5: Solve for x
   x = 73,195,224.30/9,856.87
6. Step 6: Final answer
   x = 7,425.81