Finding the Fourth Proportional to 1,139.82, 1,709.72 and 409.46

Step by Step Solution

1. Step 1: Write the proportion equation
   1,139.82 : 1,709.72 = 409.46 : x
2. Step 2: Convert to fraction form
   1,139.82/1,709.72 = 409.46/x
3. Step 3: Cross multiply
   1,139.82x = 1,709.72 × 409.46
4. Step 4: Simplify right side
   1,139.82x = 700,051.36
5. Step 5: Solve for x
   x = 700,051.36/1,139.82
6. Step 6: Final answer
   x = 614.18