Finding the Fourth Proportional to 2,108.50, 2,908.88 and 1,223.77

Step by Step Solution

1. Step 1: Write the proportion equation
   2,108.50 : 2,908.88 = 1,223.77 : x
2. Step 2: Convert to fraction form
   2,108.50/2,908.88 = 1,223.77/x
3. Step 3: Cross multiply
   2,108.50x = 2,908.88 × 1,223.77
4. Step 4: Simplify right side
   2,108.50x = 3,559,779.41
5. Step 5: Solve for x
   x = 3,559,779.41/2,108.50
6. Step 6: Final answer
   x = 1,688.30