Finding the Fourth Proportional to 1,109.28, 1,663.76 and 459.92

Step by Step Solution

1. Step 1: Write the proportion equation
   1,109.28 : 1,663.76 = 459.92 : x
2. Step 2: Convert to fraction form
   1,109.28/1,663.76 = 459.92/x
3. Step 3: Cross multiply
   1,109.28x = 1,663.76 × 459.92
4. Step 4: Simplify right side
   1,109.28x = 765,196.50
5. Step 5: Solve for x
   x = 765,196.50/1,109.28
6. Step 6: Final answer
   x = 689.81