Finding the Fourth Proportional to 1,123.72, 1,682.97 and 660.58

Step by Step Solution

1. Step 1: Write the proportion equation
   1,123.72 : 1,682.97 = 660.58 : x
2. Step 2: Convert to fraction form
   1,123.72/1,682.97 = 660.58/x
3. Step 3: Cross multiply
   1,123.72x = 1,682.97 × 660.58
4. Step 4: Simplify right side
   1,123.72x = 1,111,736.32
5. Step 5: Solve for x
   x = 1,111,736.32/1,123.72
6. Step 6: Final answer
   x = 989.34