Finding the Fourth Proportional to 1,112.32, 1,667.84 and 418.88

Step by Step Solution

1. Step 1: Write the proportion equation
   1,112.32 : 1,667.84 = 418.88 : x
2. Step 2: Convert to fraction form
   1,112.32/1,667.84 = 418.88/x
3. Step 3: Cross multiply
   1,112.32x = 1,667.84 × 418.88
4. Step 4: Simplify right side
   1,112.32x = 698,624.82
5. Step 5: Solve for x
   x = 698,624.82/1,112.32
6. Step 6: Final answer
   x = 628.08