Finding the Fourth Proportional to 39,940.32, 55,078.26 and 30,984.55

Step by Step Solution

1. Step 1: Write the proportion equation
   39,940.32 : 55,078.26 = 30,984.55 : x
2. Step 2: Convert to fraction form
   39,940.32/55,078.26 = 30,984.55/x
3. Step 3: Cross multiply
   39,940.32x = 55,078.26 × 30,984.55
4. Step 4: Simplify right side
   39,940.32x = 1,706,575,100.88
5. Step 5: Solve for x
   x = 1,706,575,100.88/39,940.32
6. Step 6: Final answer
   x = 42,728.13