Finding the Fourth Proportional to 11,902.91, 17,856.18 and 3,138.50

Step by Step Solution

1. Step 1: Write the proportion equation
   11,902.91 : 17,856.18 = 3,138.50 : x
2. Step 2: Convert to fraction form
   11,902.91/17,856.18 = 3,138.50/x
3. Step 3: Cross multiply
   11,902.91x = 17,856.18 × 3,138.50
4. Step 4: Simplify right side
   11,902.91x = 56,041,665.57
5. Step 5: Solve for x
   x = 56,041,665.57/11,902.91
6. Step 6: Final answer
   x = 4,708.23