Finding the Fourth Proportional to 1,222.43, 1,686.67 and 824.83

Step by Step Solution

1. Step 1: Write the proportion equation
   1,222.43 : 1,686.67 = 824.83 : x
2. Step 2: Convert to fraction form
   1,222.43/1,686.67 = 824.83/x
3. Step 3: Cross multiply
   1,222.43x = 1,686.67 × 824.83
4. Step 4: Simplify right side
   1,222.43x = 1,391,213.25
5. Step 5: Solve for x
   x = 1,391,213.25/1,222.43
6. Step 6: Final answer
   x = 1,138.07