Finding the Fourth Proportional to 1,665.06, 2,498.75 and 1,078.61

Step by Step Solution

1. Step 1: Write the proportion equation
   1,665.06 : 2,498.75 = 1,078.61 : x
2. Step 2: Convert to fraction form
   1,665.06/2,498.75 = 1,078.61/x
3. Step 3: Cross multiply
   1,665.06x = 2,498.75 × 1,078.61
4. Step 4: Simplify right side
   1,665.06x = 2,695,158.85
5. Step 5: Solve for x
   x = 2,695,158.85/1,665.06
6. Step 6: Final answer
   x = 1,618.66