Finding the Fourth Proportional to 1,613.71, 2,226.89 and 905.57

Step by Step Solution

1. Step 1: Write the proportion equation
   1,613.71 : 2,226.89 = 905.57 : x
2. Step 2: Convert to fraction form
   1,613.71/2,226.89 = 905.57/x
3. Step 3: Cross multiply
   1,613.71x = 2,226.89 × 905.57
4. Step 4: Simplify right side
   1,613.71x = 2,016,589.12
5. Step 5: Solve for x
   x = 2,016,589.12/1,613.71
6. Step 6: Final answer
   x = 1,249.66