Finding the Fourth Proportional to 1,139.30, 1,709.40 and 522.56

Step by Step Solution

1. Step 1: Write the proportion equation
   1,139.30 : 1,709.40 = 522.56 : x
2. Step 2: Convert to fraction form
   1,139.30/1,709.40 = 522.56/x
3. Step 3: Cross multiply
   1,139.30x = 1,709.40 × 522.56
4. Step 4: Simplify right side
   1,139.30x = 893,264.06
5. Step 5: Solve for x
   x = 893,264.06/1,139.30
6. Step 6: Final answer
   x = 784.05