Finding the Fourth Proportional to 21,838.32, 30,139.56 and 12,407.76

Step by Step Solution

1. Step 1: Write the proportion equation
   21,838.32 : 30,139.56 = 12,407.76 : x
2. Step 2: Convert to fraction form
   21,838.32/30,139.56 = 12,407.76/x
3. Step 3: Cross multiply
   21,838.32x = 30,139.56 × 12,407.76
4. Step 4: Simplify right side
   21,838.32x = 373,964,426.99
5. Step 5: Solve for x
   x = 373,964,426.99/21,838.32
6. Step 6: Final answer
   x = 17,124.23