Finding the Fourth Proportional to 21,061.72, 29,054.68 and 12,557.86

Step by Step Solution

1. Step 1: Write the proportion equation
   21,061.72 : 29,054.68 = 12,557.86 : x
2. Step 2: Convert to fraction form
   21,061.72/29,054.68 = 12,557.86/x
3. Step 3: Cross multiply
   21,061.72x = 29,054.68 × 12,557.86
4. Step 4: Simplify right side
   21,061.72x = 364,864,603.78
5. Step 5: Solve for x
   x = 364,864,603.78/21,061.72
6. Step 6: Final answer
   x = 17,323.59