Finding the Fourth Proportional to 1,553.72, 2,143.89 and 890.48

Step by Step Solution

1. Step 1: Write the proportion equation
   1,553.72 : 2,143.89 = 890.48 : x
2. Step 2: Convert to fraction form
   1,553.72/2,143.89 = 890.48/x
3. Step 3: Cross multiply
   1,553.72x = 2,143.89 × 890.48
4. Step 4: Simplify right side
   1,553.72x = 1,909,091.17
5. Step 5: Solve for x
   x = 1,909,091.17/1,553.72
6. Step 6: Final answer
   x = 1,228.72