Finding the Fourth Proportional to 28,105.38, 42,345.59 and 25,440.28

Step by Step Solution

1. Step 1: Write the proportion equation
   28,105.38 : 42,345.59 = 25,440.28 : x
2. Step 2: Convert to fraction form
   28,105.38/42,345.59 = 25,440.28/x
3. Step 3: Cross multiply
   28,105.38x = 42,345.59 × 25,440.28
4. Step 4: Simplify right side
   28,105.38x = 1,077,283,433.30
5. Step 5: Solve for x
   x = 1,077,283,433.30/28,105.38
6. Step 6: Final answer
   x = 38,330.15