Finding the Fourth Proportional to 2,124.72, 3,189.83 and 1,638.09

Step by Step Solution

1. Step 1: Write the proportion equation
   2,124.72 : 3,189.83 = 1,638.09 : x
2. Step 2: Convert to fraction form
   2,124.72/3,189.83 = 1,638.09/x
3. Step 3: Cross multiply
   2,124.72x = 3,189.83 × 1,638.09
4. Step 4: Simplify right side
   2,124.72x = 5,225,220.43
5. Step 5: Solve for x
   x = 5,225,220.43/2,124.72
6. Step 6: Final answer
   x = 2,459.25