Finding the Fourth Proportional to 12,978.71, 17,910.65 and 7,528.83

Step by Step Solution

1. Step 1: Write the proportion equation
   12,978.71 : 17,910.65 = 7,528.83 : x
2. Step 2: Convert to fraction form
   12,978.71/17,910.65 = 7,528.83/x
3. Step 3: Cross multiply
   12,978.71x = 17,910.65 × 7,528.83
4. Step 4: Simplify right side
   12,978.71x = 134,846,239.04
5. Step 5: Solve for x
   x = 134,846,239.04/12,978.71
6. Step 6: Final answer
   x = 10,389.80