Finding the Fourth Proportional to 1,003.42, 1,506.21 and 418.83

Step by Step Solution

1. Step 1: Write the proportion equation
   1,003.42 : 1,506.21 = 418.83 : x
2. Step 2: Convert to fraction form
   1,003.42/1,506.21 = 418.83/x
3. Step 3: Cross multiply
   1,003.42x = 1,506.21 × 418.83
4. Step 4: Simplify right side
   1,003.42x = 630,838.40
5. Step 5: Solve for x
   x = 630,838.40/1,003.42
6. Step 6: Final answer
   x = 628.69