Finding the Fourth Proportional to 1,123.20, 1,549.59 and 680.94

Step by Step Solution

1. Step 1: Write the proportion equation
   1,123.20 : 1,549.59 = 680.94 : x
2. Step 2: Convert to fraction form
   1,123.20/1,549.59 = 680.94/x
3. Step 3: Cross multiply
   1,123.20x = 1,549.59 × 680.94
4. Step 4: Simplify right side
   1,123.20x = 1,055,177.81
5. Step 5: Solve for x
   x = 1,055,177.81/1,123.20
6. Step 6: Final answer
   x = 939.44