Finding the Fourth Proportional to 1,139.10, 1,708.38 and 522.42

Step by Step Solution

1. Step 1: Write the proportion equation
   1,139.10 : 1,708.38 = 522.42 : x
2. Step 2: Convert to fraction form
   1,139.10/1,708.38 = 522.42/x
3. Step 3: Cross multiply
   1,139.10x = 1,708.38 × 522.42
4. Step 4: Simplify right side
   1,139.10x = 892,491.88
5. Step 5: Solve for x
   x = 892,491.88/1,139.10
6. Step 6: Final answer
   x = 783.51