Finding the Fourth Proportional to 1,209.63, 1,814.85 and 559.89

Step by Step Solution

1. Step 1: Write the proportion equation
   1,209.63 : 1,814.85 = 559.89 : x
2. Step 2: Convert to fraction form
   1,209.63/1,814.85 = 559.89/x
3. Step 3: Cross multiply
   1,209.63x = 1,814.85 × 559.89
4. Step 4: Simplify right side
   1,209.63x = 1,016,116.37
5. Step 5: Solve for x
   x = 1,016,116.37/1,209.63
6. Step 6: Final answer
   x = 840.02