Finding the Fourth Proportional to 1,665.54, 2,494.67 and 688.68

Step by Step Solution

1. Step 1: Write the proportion equation
   1,665.54 : 2,494.67 = 688.68 : x
2. Step 2: Convert to fraction form
   1,665.54/2,494.67 = 688.68/x
3. Step 3: Cross multiply
   1,665.54x = 2,494.67 × 688.68
4. Step 4: Simplify right side
   1,665.54x = 1,718,025.89
5. Step 5: Solve for x
   x = 1,718,025.89/1,665.54
6. Step 6: Final answer
   x = 1,031.51