Finding the Fourth Proportional to 1,222.55, 1,686.98 and 698.48

Step by Step Solution

1. Step 1: Write the proportion equation
   1,222.55 : 1,686.98 = 698.48 : x
2. Step 2: Convert to fraction form
   1,222.55/1,686.98 = 698.48/x
3. Step 3: Cross multiply
   1,222.55x = 1,686.98 × 698.48
4. Step 4: Simplify right side
   1,222.55x = 1,178,309.86
5. Step 5: Solve for x
   x = 1,178,309.86/1,222.55
6. Step 6: Final answer
   x = 963.82