Finding the Fourth Proportional to 1,580.98, 2,181.72 and 872.89

Step by Step Solution

1. Step 1: Write the proportion equation
   1,580.98 : 2,181.72 = 872.89 : x
2. Step 2: Convert to fraction form
   1,580.98/2,181.72 = 872.89/x
3. Step 3: Cross multiply
   1,580.98x = 2,181.72 × 872.89
4. Step 4: Simplify right side
   1,580.98x = 1,904,401.57
5. Step 5: Solve for x
   x = 1,904,401.57/1,580.98
6. Step 6: Final answer
   x = 1,204.57