Finding the Fourth Proportional to 1,223.02, 1,687.76 and 699.06

Step by Step Solution

1. Step 1: Write the proportion equation
   1,223.02 : 1,687.76 = 699.06 : x
2. Step 2: Convert to fraction form
   1,223.02/1,687.76 = 699.06/x
3. Step 3: Cross multiply
   1,223.02x = 1,687.76 × 699.06
4. Step 4: Simplify right side
   1,223.02x = 1,179,843.43
5. Step 5: Solve for x
   x = 1,179,843.43/1,223.02
6. Step 6: Final answer
   x = 964.70