Finding the Fourth Proportional to 21,641.80, 29,865.72 and 12,211.24

Step by Step Solution

1. Step 1: Write the proportion equation
   21,641.80 : 29,865.72 = 12,211.24 : x
2. Step 2: Convert to fraction form
   21,641.80/29,865.72 = 12,211.24/x
3. Step 3: Cross multiply
   21,641.80x = 29,865.72 × 12,211.24
4. Step 4: Simplify right side
   21,641.80x = 364,697,518.83
5. Step 5: Solve for x
   x = 364,697,518.83/21,641.80
6. Step 6: Final answer
   x = 16,851.53