Finding the Fourth Proportional to 1,111.52, 1,666.58 and 418.16

Step by Step Solution

1. Step 1: Write the proportion equation
   1,111.52 : 1,666.58 = 418.16 : x
2. Step 2: Convert to fraction form
   1,111.52/1,666.58 = 418.16/x
3. Step 3: Cross multiply
   1,111.52x = 1,666.58 × 418.16
4. Step 4: Simplify right side
   1,111.52x = 696,899.17
5. Step 5: Solve for x
   x = 696,899.17/1,111.52
6. Step 6: Final answer
   x = 626.98