Finding the Fourth Proportional to 33,638.72, 50,402.72 and 20,451.20

Step by Step Solution

1. Step 1: Write the proportion equation
   33,638.72 : 50,402.72 = 20,451.20 : x
2. Step 2: Convert to fraction form
   33,638.72/50,402.72 = 20,451.20/x
3. Step 3: Cross multiply
   33,638.72x = 50,402.72 × 20,451.20
4. Step 4: Simplify right side
   33,638.72x = 1,030,796,107.26
5. Step 5: Solve for x
   x = 1,030,796,107.26/33,638.72
6. Step 6: Final answer
   x = 30,643.14