Finding the Fourth Proportional to 3,086.78, 4,259.79 and 1,689.50

Step by Step Solution

1. Step 1: Write the proportion equation
   3,086.78 : 4,259.79 = 1,689.50 : x
2. Step 2: Convert to fraction form
   3,086.78/4,259.79 = 1,689.50/x
3. Step 3: Cross multiply
   3,086.78x = 4,259.79 × 1,689.50
4. Step 4: Simplify right side
   3,086.78x = 7,196,915.21
5. Step 5: Solve for x
   x = 7,196,915.21/3,086.78
6. Step 6: Final answer
   x = 2,331.53