Finding the Fourth Proportional to 12,225.30, 18,305.10 and 7,758.78

Step by Step Solution

1. Step 1: Write the proportion equation
   12,225.30 : 18,305.10 = 7,758.78 : x
2. Step 2: Convert to fraction form
   12,225.30/18,305.10 = 7,758.78/x
3. Step 3: Cross multiply
   12,225.30x = 18,305.10 × 7,758.78
4. Step 4: Simplify right side
   12,225.30x = 142,025,283.33
5. Step 5: Solve for x
   x = 142,025,283.33/12,225.30
6. Step 6: Final answer
   x = 11,617.33