Finding the Fourth Proportional to 1,223.89, 1,688.94 and 692.77

Step by Step Solution

1. Step 1: Write the proportion equation
   1,223.89 : 1,688.94 = 692.77 : x
2. Step 2: Convert to fraction form
   1,223.89/1,688.94 = 692.77/x
3. Step 3: Cross multiply
   1,223.89x = 1,688.94 × 692.77
4. Step 4: Simplify right side
   1,223.89x = 1,170,046.96
5. Step 5: Solve for x
   x = 1,170,046.96/1,223.89
6. Step 6: Final answer
   x = 956.01