Finding the Fourth Proportional to 1,354.86, 2,031.87 and 688.05

Step by Step Solution

1. Step 1: Write the proportion equation
   1,354.86 : 2,031.87 = 688.05 : x
2. Step 2: Convert to fraction form
   1,354.86/2,031.87 = 688.05/x
3. Step 3: Cross multiply
   1,354.86x = 2,031.87 × 688.05
4. Step 4: Simplify right side
   1,354.86x = 1,398,028.15
5. Step 5: Solve for x
   x = 1,398,028.15/1,354.86
6. Step 6: Final answer
   x = 1,031.86