Finding the Fourth Proportional to 21,471.94, 29,630.56 and 12,972.58

Step by Step Solution

1. Step 1: Write the proportion equation
   21,471.94 : 29,630.56 = 12,972.58 : x
2. Step 2: Convert to fraction form
   21,471.94/29,630.56 = 12,972.58/x
3. Step 3: Cross multiply
   21,471.94x = 29,630.56 × 12,972.58
4. Step 4: Simplify right side
   21,471.94x = 384,384,810.04
5. Step 5: Solve for x
   x = 384,384,810.04/21,471.94
6. Step 6: Final answer
   x = 17,901.73