Finding the Fourth Proportional to 1,109.55, 1,664.98 and 416.71

Step by Step Solution

1. Step 1: Write the proportion equation
   1,109.55 : 1,664.98 = 416.71 : x
2. Step 2: Convert to fraction form
   1,109.55/1,664.98 = 416.71/x
3. Step 3: Cross multiply
   1,109.55x = 1,664.98 × 416.71
4. Step 4: Simplify right side
   1,109.55x = 693,813.82
5. Step 5: Solve for x
   x = 693,813.82/1,109.55
6. Step 6: Final answer
   x = 625.31