Finding the Fourth Proportional to 1,392.34, 2,086.98 and 660.82

Step by Step Solution

1. Step 1: Write the proportion equation
   1,392.34 : 2,086.98 = 660.82 : x
2. Step 2: Convert to fraction form
   1,392.34/2,086.98 = 660.82/x
3. Step 3: Cross multiply
   1,392.34x = 2,086.98 × 660.82
4. Step 4: Simplify right side
   1,392.34x = 1,379,118.12
5. Step 5: Solve for x
   x = 1,379,118.12/1,392.34
6. Step 6: Final answer
   x = 990.50