Finding the Fourth Proportional to 13,280.72, 18,327.42 and 7,312.80

Step by Step Solution

1. Step 1: Write the proportion equation
   13,280.72 : 18,327.42 = 7,312.80 : x
2. Step 2: Convert to fraction form
   13,280.72/18,327.42 = 7,312.80/x
3. Step 3: Cross multiply
   13,280.72x = 18,327.42 × 7,312.80
4. Step 4: Simplify right side
   13,280.72x = 134,024,756.98
5. Step 5: Solve for x
   x = 134,024,756.98/13,280.72
6. Step 6: Final answer
   x = 10,091.68