Finding the Fourth Proportional to 39,411.96, 54,388.56 and 21,507.31

Step by Step Solution

1. Step 1: Write the proportion equation
   39,411.96 : 54,388.56 = 21,507.31 : x
2. Step 2: Convert to fraction form
   39,411.96/54,388.56 = 21,507.31/x
3. Step 3: Cross multiply
   39,411.96x = 54,388.56 × 21,507.31
4. Step 4: Simplify right side
   39,411.96x = 1,169,751,620.37
5. Step 5: Solve for x
   x = 1,169,751,620.37/39,411.96
6. Step 6: Final answer
   x = 29,680.12