Finding the Fourth Proportional to 1,038.31, 1,557.46 and 712.69

Step by Step Solution

1. Step 1: Write the proportion equation
   1,038.31 : 1,557.46 = 712.69 : x
2. Step 2: Convert to fraction form
   1,038.31/1,557.46 = 712.69/x
3. Step 3: Cross multiply
   1,038.31x = 1,557.46 × 712.69
4. Step 4: Simplify right side
   1,038.31x = 1,109,986.17
5. Step 5: Solve for x
   x = 1,109,986.17/1,038.31
6. Step 6: Final answer
   x = 1,069.03