Finding the Fourth Proportional to 1,111.09, 1,666.32 and 417.25

Step by Step Solution

1. Step 1: Write the proportion equation
   1,111.09 : 1,666.32 = 417.25 : x
2. Step 2: Convert to fraction form
   1,111.09/1,666.32 = 417.25/x
3. Step 3: Cross multiply
   1,111.09x = 1,666.32 × 417.25
4. Step 4: Simplify right side
   1,111.09x = 695,274.89
5. Step 5: Solve for x
   x = 695,274.89/1,111.09
6. Step 6: Final answer
   x = 625.76