Finding the Fourth Proportional to 2,005.39, 3,007.34 and 688.77

Step by Step Solution

1. Step 1: Write the proportion equation
   2,005.39 : 3,007.34 = 688.77 : x
2. Step 2: Convert to fraction form
   2,005.39/3,007.34 = 688.77/x
3. Step 3: Cross multiply
   2,005.39x = 3,007.34 × 688.77
4. Step 4: Simplify right side
   2,005.39x = 2,071,362.13
5. Step 5: Solve for x
   x = 2,071,362.13/2,005.39
6. Step 6: Final answer
   x = 1,032.90