Finding the Fourth Proportional to 1,223.06, 1,687.73 and 699.02

Step by Step Solution

1. Step 1: Write the proportion equation
   1,223.06 : 1,687.73 = 699.02 : x
2. Step 2: Convert to fraction form
   1,223.06/1,687.73 = 699.02/x
3. Step 3: Cross multiply
   1,223.06x = 1,687.73 × 699.02
4. Step 4: Simplify right side
   1,223.06x = 1,179,757.02
5. Step 5: Solve for x
   x = 1,179,757.02/1,223.06
6. Step 6: Final answer
   x = 964.59