Finding the Fourth Proportional to 2,107.56, 2,907.82 and 1,223.56

Step by Step Solution

1. Step 1: Write the proportion equation
   2,107.56 : 2,907.82 = 1,223.56 : x
2. Step 2: Convert to fraction form
   2,107.56/2,907.82 = 1,223.56/x
3. Step 3: Cross multiply
   2,107.56x = 2,907.82 × 1,223.56
4. Step 4: Simplify right side
   2,107.56x = 3,557,892.24
5. Step 5: Solve for x
   x = 3,557,892.24/2,107.56
6. Step 6: Final answer
   x = 1,688.16