Finding the Fourth Proportional to 11,906.91, 16,428.24 and 6,870.78

Step by Step Solution

1. Step 1: Write the proportion equation
   11,906.91 : 16,428.24 = 6,870.78 : x
2. Step 2: Convert to fraction form
   11,906.91/16,428.24 = 6,870.78/x
3. Step 3: Cross multiply
   11,906.91x = 16,428.24 × 6,870.78
4. Step 4: Simplify right side
   11,906.91x = 112,874,822.83
5. Step 5: Solve for x
   x = 112,874,822.83/11,906.91
6. Step 6: Final answer
   x = 9,479.77