Finding the Fourth Proportional to 1,086.39, 1,498.50 and 693.90

Step by Step Solution

1. Step 1: Write the proportion equation
   1,086.39 : 1,498.50 = 693.90 : x
2. Step 2: Convert to fraction form
   1,086.39/1,498.50 = 693.90/x
3. Step 3: Cross multiply
   1,086.39x = 1,498.50 × 693.90
4. Step 4: Simplify right side
   1,086.39x = 1,039,809.15
5. Step 5: Solve for x
   x = 1,039,809.15/1,086.39
6. Step 6: Final answer
   x = 957.12