Finding the Fourth Proportional to 1,111.14, 1,667.55 and 418.46

Step by Step Solution

1. Step 1: Write the proportion equation
   1,111.14 : 1,667.55 = 418.46 : x
2. Step 2: Convert to fraction form
   1,111.14/1,667.55 = 418.46/x
3. Step 3: Cross multiply
   1,111.14x = 1,667.55 × 418.46
4. Step 4: Simplify right side
   1,111.14x = 697,794.64
5. Step 5: Solve for x
   x = 697,794.64/1,111.14
6. Step 6: Final answer
   x = 628.00