Finding the Fourth Proportional to 1,039.98, 1,435.59 and 647.55

Step by Step Solution

1. Step 1: Write the proportion equation
   1,039.98 : 1,435.59 = 647.55 : x
2. Step 2: Convert to fraction form
   1,039.98/1,435.59 = 647.55/x
3. Step 3: Cross multiply
   1,039.98x = 1,435.59 × 647.55
4. Step 4: Simplify right side
   1,039.98x = 929,616.30
5. Step 5: Solve for x
   x = 929,616.30/1,039.98
6. Step 6: Final answer
   x = 893.88