Finding the Fourth Proportional to 10,557.47, 15,819.78 and 3,980.07

Step by Step Solution

1. Step 1: Write the proportion equation
   10,557.47 : 15,819.78 = 3,980.07 : x
2. Step 2: Convert to fraction form
   10,557.47/15,819.78 = 3,980.07/x
3. Step 3: Cross multiply
   10,557.47x = 15,819.78 × 3,980.07
4. Step 4: Simplify right side
   10,557.47x = 62,963,752.69
5. Step 5: Solve for x
   x = 62,963,752.69/10,557.47
6. Step 6: Final answer
   x = 5,963.91