Finding the Fourth Proportional to 2,160.40, 3,238.56 and 698.80

Step by Step Solution

1. Step 1: Write the proportion equation
   2,160.40 : 3,238.56 = 698.80 : x
2. Step 2: Convert to fraction form
   2,160.40/3,238.56 = 698.80/x
3. Step 3: Cross multiply
   2,160.40x = 3,238.56 × 698.80
4. Step 4: Simplify right side
   2,160.40x = 2,263,105.73
5. Step 5: Solve for x
   x = 2,263,105.73/2,160.40
6. Step 6: Final answer
   x = 1,047.54