Finding the Fourth Proportional to 1,222.07, 1,686.42 and 698.06

Step by Step Solution

1. Step 1: Write the proportion equation
   1,222.07 : 1,686.42 = 698.06 : x
2. Step 2: Convert to fraction form
   1,222.07/1,686.42 = 698.06/x
3. Step 3: Cross multiply
   1,222.07x = 1,686.42 × 698.06
4. Step 4: Simplify right side
   1,222.07x = 1,177,226.56
5. Step 5: Solve for x
   x = 1,177,226.56/1,222.07
6. Step 6: Final answer
   x = 963.31