Finding the Fourth Proportional to 12,621.60, 17,400.24 and 7,902.72

Step by Step Solution

1. Step 1: Write the proportion equation
   12,621.60 : 17,400.24 = 7,902.72 : x
2. Step 2: Convert to fraction form
   12,621.60/17,400.24 = 7,902.72/x
3. Step 3: Cross multiply
   12,621.60x = 17,400.24 × 7,902.72
4. Step 4: Simplify right side
   12,621.60x = 137,509,224.65
5. Step 5: Solve for x
   x = 137,509,224.65/12,621.60
6. Step 6: Final answer
   x = 10,894.75