Finding the Fourth Proportional to 1,109.23, 1,662.71 and 415.42

Step by Step Solution

1. Step 1: Write the proportion equation
   1,109.23 : 1,662.71 = 415.42 : x
2. Step 2: Convert to fraction form
   1,109.23/1,662.71 = 415.42/x
3. Step 3: Cross multiply
   1,109.23x = 1,662.71 × 415.42
4. Step 4: Simplify right side
   1,109.23x = 690,722.99
5. Step 5: Solve for x
   x = 690,722.99/1,109.23
6. Step 6: Final answer
   x = 622.70