Finding the Fourth Proportional to 1,223.03, 1,687.86 and 699.05

Step by Step Solution

1. Step 1: Write the proportion equation
   1,223.03 : 1,687.86 = 699.05 : x
2. Step 2: Convert to fraction form
   1,223.03/1,687.86 = 699.05/x
3. Step 3: Cross multiply
   1,223.03x = 1,687.86 × 699.05
4. Step 4: Simplify right side
   1,223.03x = 1,179,902.75
5. Step 5: Solve for x
   x = 1,179,902.75/1,223.03
6. Step 6: Final answer
   x = 964.74