Finding the Fourth Proportional to 2,287.47, 3,156.72 and 1,239.54

Step by Step Solution

1. Step 1: Write the proportion equation
   2,287.47 : 3,156.72 = 1,239.54 : x
2. Step 2: Convert to fraction form
   2,287.47/3,156.72 = 1,239.54/x
3. Step 3: Cross multiply
   2,287.47x = 3,156.72 × 1,239.54
4. Step 4: Simplify right side
   2,287.47x = 3,912,880.71
5. Step 5: Solve for x
   x = 3,912,880.71/2,287.47
6. Step 6: Final answer
   x = 1,710.57