Finding the Fourth Proportional to 16,259.20, 21,880.64 and 16,259.20

Step by Step Solution

1. Step 1: Write the proportion equation
   16,259.20 : 21,880.64 = 16,259.20 : x
2. Step 2: Convert to fraction form
   16,259.20/21,880.64 = 16,259.20/x
3. Step 3: Cross multiply
   16,259.20x = 21,880.64 × 16,259.20
4. Step 4: Simplify right side
   16,259.20x = 355,761,701.89
5. Step 5: Solve for x
   x = 355,761,701.89/16,259.20
6. Step 6: Final answer
   x = 21,880.64