Finding the Fourth Proportional to 21,904.04, 30,216.72 and 12,947.24

Step by Step Solution

1. Step 1: Write the proportion equation
   21,904.04 : 30,216.72 = 12,947.24 : x
2. Step 2: Convert to fraction form
   21,904.04/30,216.72 = 12,947.24/x
3. Step 3: Cross multiply
   21,904.04x = 30,216.72 × 12,947.24
4. Step 4: Simplify right side
   21,904.04x = 391,223,125.85
5. Step 5: Solve for x
   x = 391,223,125.85/21,904.04
6. Step 6: Final answer
   x = 17,860.77