Finding the Fourth Proportional to 1,105.98, 1,659.20 and 456.78

Step by Step Solution

1. Step 1: Write the proportion equation
   1,105.98 : 1,659.20 = 456.78 : x
2. Step 2: Convert to fraction form
   1,105.98/1,659.20 = 456.78/x
3. Step 3: Cross multiply
   1,105.98x = 1,659.20 × 456.78
4. Step 4: Simplify right side
   1,105.98x = 757,889.38
5. Step 5: Solve for x
   x = 757,889.38/1,105.98
6. Step 6: Final answer
   x = 685.26