Finding the Fourth Proportional to 2,139.72, 3,208.34 and 1,042.98

Step by Step Solution

1. Step 1: Write the proportion equation
   2,139.72 : 3,208.34 = 1,042.98 : x
2. Step 2: Convert to fraction form
   2,139.72/3,208.34 = 1,042.98/x
3. Step 3: Cross multiply
   2,139.72x = 3,208.34 × 1,042.98
4. Step 4: Simplify right side
   2,139.72x = 3,346,234.45
5. Step 5: Solve for x
   x = 3,346,234.45/2,139.72
6. Step 6: Final answer
   x = 1,563.87