Finding the Fourth Proportional to 758.89, 1,139.42 and 724.06

Step by Step Solution

1. Step 1: Write the proportion equation
   758.89 : 1,139.42 = 724.06 : x
2. Step 2: Convert to fraction form
   758.89/1,139.42 = 724.06/x
3. Step 3: Cross multiply
   758.89x = 1,139.42 × 724.06
4. Step 4: Simplify right side
   758.89x = 825,008.45
5. Step 5: Solve for x
   x = 825,008.45/758.89
6. Step 6: Final answer
   x = 1,087.13