Finding the Fourth Proportional to 21,056.15, 29,058.82 and 12,105.05

Step by Step Solution

1. Step 1: Write the proportion equation
   21,056.15 : 29,058.82 = 12,105.05 : x
2. Step 2: Convert to fraction form
   21,056.15/29,058.82 = 12,105.05/x
3. Step 3: Cross multiply
   21,056.15x = 29,058.82 × 12,105.05
4. Step 4: Simplify right side
   21,056.15x = 351,758,293.48
5. Step 5: Solve for x
   x = 351,758,293.48/21,056.15
6. Step 6: Final answer
   x = 16,705.73