Finding the Fourth Proportional to 1,054.18, 1,580.96 and 404.76

Step by Step Solution

1. Step 1: Write the proportion equation
   1,054.18 : 1,580.96 = 404.76 : x
2. Step 2: Convert to fraction form
   1,054.18/1,580.96 = 404.76/x
3. Step 3: Cross multiply
   1,054.18x = 1,580.96 × 404.76
4. Step 4: Simplify right side
   1,054.18x = 639,909.37
5. Step 5: Solve for x
   x = 639,909.37/1,054.18
6. Step 6: Final answer
   x = 607.02