Finding the Fourth Proportional to 2,085.40, 3,128.22 and 698.92

Step by Step Solution

1. Step 1: Write the proportion equation
   2,085.40 : 3,128.22 = 698.92 : x
2. Step 2: Convert to fraction form
   2,085.40/3,128.22 = 698.92/x
3. Step 3: Cross multiply
   2,085.40x = 3,128.22 × 698.92
4. Step 4: Simplify right side
   2,085.40x = 2,186,375.52
5. Step 5: Solve for x
   x = 2,186,375.52/2,085.40
6. Step 6: Final answer
   x = 1,048.42