Finding the Fourth Proportional to 2,107.42, 2,908.11 and 1,223.50

Step by Step Solution

1. Step 1: Write the proportion equation
   2,107.42 : 2,908.11 = 1,223.50 : x
2. Step 2: Convert to fraction form
   2,107.42/2,908.11 = 1,223.50/x
3. Step 3: Cross multiply
   2,107.42x = 2,908.11 × 1,223.50
4. Step 4: Simplify right side
   2,107.42x = 3,558,072.59
5. Step 5: Solve for x
   x = 3,558,072.59/2,107.42
6. Step 6: Final answer
   x = 1,688.35