Finding the Fourth Proportional to 13,072.61, 18,037.28 and 7,406.87

Step by Step Solution

1. Step 1: Write the proportion equation
   13,072.61 : 18,037.28 = 7,406.87 : x
2. Step 2: Convert to fraction form
   13,072.61/18,037.28 = 7,406.87/x
3. Step 3: Cross multiply
   13,072.61x = 18,037.28 × 7,406.87
4. Step 4: Simplify right side
   13,072.61x = 133,599,660.89
5. Step 5: Solve for x
   x = 133,599,660.89/13,072.61
6. Step 6: Final answer
   x = 10,219.82