Finding the Fourth Proportional to 1,079.06, 1,489.59 and 686.61

Step by Step Solution

1. Step 1: Write the proportion equation
   1,079.06 : 1,489.59 = 686.61 : x
2. Step 2: Convert to fraction form
   1,079.06/1,489.59 = 686.61/x
3. Step 3: Cross multiply
   1,079.06x = 1,489.59 × 686.61
4. Step 4: Simplify right side
   1,079.06x = 1,022,767.39
5. Step 5: Solve for x
   x = 1,022,767.39/1,079.06
6. Step 6: Final answer
   x = 947.84