Finding the Fourth Proportional to 1,424.39, 2,137.59 and 808.65

Step by Step Solution

1. Step 1: Write the proportion equation
   1,424.39 : 2,137.59 = 808.65 : x
2. Step 2: Convert to fraction form
   1,424.39/2,137.59 = 808.65/x
3. Step 3: Cross multiply
   1,424.39x = 2,137.59 × 808.65
4. Step 4: Simplify right side
   1,424.39x = 1,728,562.15
5. Step 5: Solve for x
   x = 1,728,562.15/1,424.39
6. Step 6: Final answer
   x = 1,213.55