Finding the Fourth Proportional to 1,139.24, 1,572.18 and 697.39

Step by Step Solution

1. Step 1: Write the proportion equation
   1,139.24 : 1,572.18 = 697.39 : x
2. Step 2: Convert to fraction form
   1,139.24/1,572.18 = 697.39/x
3. Step 3: Cross multiply
   1,139.24x = 1,572.18 × 697.39
4. Step 4: Simplify right side
   1,139.24x = 1,096,422.61
5. Step 5: Solve for x
   x = 1,096,422.61/1,139.24
6. Step 6: Final answer
   x = 962.42