Finding the Fourth Proportional to 1,139.47, 1,573.41 and 720.52

Step by Step Solution

1. Step 1: Write the proportion equation
   1,139.47 : 1,573.41 = 720.52 : x
2. Step 2: Convert to fraction form
   1,139.47/1,573.41 = 720.52/x
3. Step 3: Cross multiply
   1,139.47x = 1,573.41 × 720.52
4. Step 4: Simplify right side
   1,139.47x = 1,133,673.37
5. Step 5: Solve for x
   x = 1,133,673.37/1,139.47
6. Step 6: Final answer
   x = 994.91