Finding the Fourth Proportional to 1,077.89, 1,618.89 and 669.88

Step by Step Solution

1. Step 1: Write the proportion equation
   1,077.89 : 1,618.89 = 669.88 : x
2. Step 2: Convert to fraction form
   1,077.89/1,618.89 = 669.88/x
3. Step 3: Cross multiply
   1,077.89x = 1,618.89 × 669.88
4. Step 4: Simplify right side
   1,077.89x = 1,084,464.06
5. Step 5: Solve for x
   x = 1,084,464.06/1,077.89
6. Step 6: Final answer
   x = 1,006.10