Finding the Fourth Proportional to 39,881.33, 55,038.65 and 21,976.31

Step by Step Solution

1. Step 1: Write the proportion equation
   39,881.33 : 55,038.65 = 21,976.31 : x
2. Step 2: Convert to fraction form
   39,881.33/55,038.65 = 21,976.31/x
3. Step 3: Cross multiply
   39,881.33x = 55,038.65 × 21,976.31
4. Step 4: Simplify right side
   39,881.33x = 1,209,546,462.10
5. Step 5: Solve for x
   x = 1,209,546,462.10/39,881.33
6. Step 6: Final answer
   x = 30,328.64