Finding the Fourth Proportional to 10,645.83, 15,978.59 and 5,384.57

Step by Step Solution

1. Step 1: Write the proportion equation
   10,645.83 : 15,978.59 = 5,384.57 : x
2. Step 2: Convert to fraction form
   10,645.83/15,978.59 = 5,384.57/x
3. Step 3: Cross multiply
   10,645.83x = 15,978.59 × 5,384.57
4. Step 4: Simplify right side
   10,645.83x = 86,037,729.54
5. Step 5: Solve for x
   x = 86,037,729.54/10,645.83
6. Step 6: Final answer
   x = 8,081.82