Finding the Fourth Proportional to 1,426.38, 2,136.78 and 808.20

Step by Step Solution

1. Step 1: Write the proportion equation
   1,426.38 : 2,136.78 = 808.20 : x
2. Step 2: Convert to fraction form
   1,426.38/2,136.78 = 808.20/x
3. Step 3: Cross multiply
   1,426.38x = 2,136.78 × 808.20
4. Step 4: Simplify right side
   1,426.38x = 1,726,945.60
5. Step 5: Solve for x
   x = 1,726,945.60/1,426.38
6. Step 6: Final answer
   x = 1,210.72