Finding the Fourth Proportional to 12,145.30, 18,216.42 and 3,380.89

Step by Step Solution

1. Step 1: Write the proportion equation
   12,145.30 : 18,216.42 = 3,380.89 : x
2. Step 2: Convert to fraction form
   12,145.30/18,216.42 = 3,380.89/x
3. Step 3: Cross multiply
   12,145.30x = 18,216.42 × 3,380.89
4. Step 4: Simplify right side
   12,145.30x = 61,587,712.21
5. Step 5: Solve for x
   x = 61,587,712.21/12,145.30
6. Step 6: Final answer
   x = 5,070.91