Finding the Fourth Proportional to 1,985.01, 2,978.00 and 686.49

Step by Step Solution

1. Step 1: Write the proportion equation
   1,985.01 : 2,978.00 = 686.49 : x
2. Step 2: Convert to fraction form
   1,985.01/2,978.00 = 686.49/x
3. Step 3: Cross multiply
   1,985.01x = 2,978.00 × 686.49
4. Step 4: Simplify right side
   1,985.01x = 2,044,363.79
5. Step 5: Solve for x
   x = 2,044,363.79/1,985.01
6. Step 6: Final answer
   x = 1,029.90