Finding the Fourth Proportional to 1,105.80, 1,659.48 and 817.92

Step by Step Solution

1. Step 1: Write the proportion equation
   1,105.80 : 1,659.48 = 817.92 : x
2. Step 2: Convert to fraction form
   1,105.80/1,659.48 = 817.92/x
3. Step 3: Cross multiply
   1,105.80x = 1,659.48 × 817.92
4. Step 4: Simplify right side
   1,105.80x = 1,357,321.88
5. Step 5: Solve for x
   x = 1,357,321.88/1,105.80
6. Step 6: Final answer
   x = 1,227.46