Finding the Fourth Proportional to 1,378.76, 2,067.71 and 404.62

Step by Step Solution

1. Step 1: Write the proportion equation
   1,378.76 : 2,067.71 = 404.62 : x
2. Step 2: Convert to fraction form
   1,378.76/2,067.71 = 404.62/x
3. Step 3: Cross multiply
   1,378.76x = 2,067.71 × 404.62
4. Step 4: Simplify right side
   1,378.76x = 836,636.82
5. Step 5: Solve for x
   x = 836,636.82/1,378.76
6. Step 6: Final answer
   x = 606.80