Finding the Fourth Proportional to 1,139.25, 1,709.12 and 369.81

Step by Step Solution

1. Step 1: Write the proportion equation
   1,139.25 : 1,709.12 = 369.81 : x
2. Step 2: Convert to fraction form
   1,139.25/1,709.12 = 369.81/x
3. Step 3: Cross multiply
   1,139.25x = 1,709.12 × 369.81
4. Step 4: Simplify right side
   1,139.25x = 632,047.82
5. Step 5: Solve for x
   x = 632,047.82/1,139.25
6. Step 6: Final answer
   x = 554.79