Finding the Fourth Proportional to 12,156.99, 18,238.56 and 3,391.91

Step by Step Solution

1. Step 1: Write the proportion equation
   12,156.99 : 18,238.56 = 3,391.91 : x
2. Step 2: Convert to fraction form
   12,156.99/18,238.56 = 3,391.91/x
3. Step 3: Cross multiply
   12,156.99x = 18,238.56 × 3,391.91
4. Step 4: Simplify right side
   12,156.99x = 61,863,462.86
5. Step 5: Solve for x
   x = 61,863,462.86/12,156.99
6. Step 6: Final answer
   x = 5,088.72