Finding the Fourth Proportional to 2,072.56, 3,109.22 and 685.98

Step by Step Solution

1. Step 1: Write the proportion equation
   2,072.56 : 3,109.22 = 685.98 : x
2. Step 2: Convert to fraction form
   2,072.56/3,109.22 = 685.98/x
3. Step 3: Cross multiply
   2,072.56x = 3,109.22 × 685.98
4. Step 4: Simplify right side
   2,072.56x = 2,132,862.74
5. Step 5: Solve for x
   x = 2,132,862.74/2,072.56
6. Step 6: Final answer
   x = 1,029.10