Finding the Fourth Proportional to 2,287.59, 3,156.88 and 1,239.66

Step by Step Solution

1. Step 1: Write the proportion equation
   2,287.59 : 3,156.88 = 1,239.66 : x
2. Step 2: Convert to fraction form
   2,287.59/3,156.88 = 1,239.66/x
3. Step 3: Cross multiply
   2,287.59x = 3,156.88 × 1,239.66
4. Step 4: Simplify right side
   2,287.59x = 3,913,445.25
5. Step 5: Solve for x
   x = 3,913,445.25/2,287.59
6. Step 6: Final answer
   x = 1,710.73