Finding the Fourth Proportional to 2,287.38, 3,156.59 and 1,239.45

Step by Step Solution

1. Step 1: Write the proportion equation
   2,287.38 : 3,156.59 = 1,239.45 : x
2. Step 2: Convert to fraction form
   2,287.38/3,156.59 = 1,239.45/x
3. Step 3: Cross multiply
   2,287.38x = 3,156.59 × 1,239.45
4. Step 4: Simplify right side
   2,287.38x = 3,912,435.48
5. Step 5: Solve for x
   x = 3,912,435.48/2,287.38
6. Step 6: Final answer
   x = 1,710.44