Finding the Fourth Proportional to 3,404.72, 5,107.20 and 939.72

Step by Step Solution

1. Step 1: Write the proportion equation
   3,404.72 : 5,107.20 = 939.72 : x
2. Step 2: Convert to fraction form
   3,404.72/5,107.20 = 939.72/x
3. Step 3: Cross multiply
   3,404.72x = 5,107.20 × 939.72
4. Step 4: Simplify right side
   3,404.72x = 4,799,337.98
5. Step 5: Solve for x
   x = 4,799,337.98/3,404.72
6. Step 6: Final answer
   x = 1,409.61