Finding the Fourth Proportional to 1,404.63, 2,108.85 and 820.23

Step by Step Solution

1. Step 1: Write the proportion equation
   1,404.63 : 2,108.85 = 820.23 : x
2. Step 2: Convert to fraction form
   1,404.63/2,108.85 = 820.23/x
3. Step 3: Cross multiply
   1,404.63x = 2,108.85 × 820.23
4. Step 4: Simplify right side
   1,404.63x = 1,729,742.04
5. Step 5: Solve for x
   x = 1,729,742.04/1,404.63
6. Step 6: Final answer
   x = 1,231.46