Finding the Fourth Proportional to 1,039.17, 1,559.31 and 692.69

Step by Step Solution

1. Step 1: Write the proportion equation
   1,039.17 : 1,559.31 = 692.69 : x
2. Step 2: Convert to fraction form
   1,039.17/1,559.31 = 692.69/x
3. Step 3: Cross multiply
   1,039.17x = 1,559.31 × 692.69
4. Step 4: Simplify right side
   1,039.17x = 1,080,120.72
5. Step 5: Solve for x
   x = 1,080,120.72/1,039.17
6. Step 6: Final answer
   x = 1,039.41