Finding the Fourth Proportional to 1,078.72, 1,617.92 and 670.48

Step by Step Solution

1. Step 1: Write the proportion equation
   1,078.72 : 1,617.92 = 670.48 : x
2. Step 2: Convert to fraction form
   1,078.72/1,617.92 = 670.48/x
3. Step 3: Cross multiply
   1,078.72x = 1,617.92 × 670.48
4. Step 4: Simplify right side
   1,078.72x = 1,084,781.89
5. Step 5: Solve for x
   x = 1,084,781.89/1,078.72
6. Step 6: Final answer
   x = 1,005.62