Finding the Fourth Proportional to 21,061.61, 29,054.52 and 12,557.74

Step by Step Solution

1. Step 1: Write the proportion equation
   21,061.61 : 29,054.52 = 12,557.74 : x
2. Step 2: Convert to fraction form
   21,061.61/29,054.52 = 12,557.74/x
3. Step 3: Cross multiply
   21,061.61x = 29,054.52 × 12,557.74
4. Step 4: Simplify right side
   21,061.61x = 364,859,107.98
5. Step 5: Solve for x
   x = 364,859,107.98/21,061.61
6. Step 6: Final answer
   x = 17,323.42