Finding the Fourth Proportional to 1,139.34, 1,572.36 and 691.52

Step by Step Solution

1. Step 1: Write the proportion equation
   1,139.34 : 1,572.36 = 691.52 : x
2. Step 2: Convert to fraction form
   1,139.34/1,572.36 = 691.52/x
3. Step 3: Cross multiply
   1,139.34x = 1,572.36 × 691.52
4. Step 4: Simplify right side
   1,139.34x = 1,087,327.30
5. Step 5: Solve for x
   x = 1,087,327.30/1,139.34
6. Step 6: Final answer
   x = 954.35