Finding the Fourth Proportional to 1,222.91, 1,687.49 and 698.93

Step by Step Solution

1. Step 1: Write the proportion equation
   1,222.91 : 1,687.49 = 698.93 : x
2. Step 2: Convert to fraction form
   1,222.91/1,687.49 = 698.93/x
3. Step 3: Cross multiply
   1,222.91x = 1,687.49 × 698.93
4. Step 4: Simplify right side
   1,222.91x = 1,179,433.89
5. Step 5: Solve for x
   x = 1,179,433.89/1,222.91
6. Step 6: Final answer
   x = 964.45