Finding the Fourth Proportional to 1,189.64, 1,641.71 and 658.56

Step by Step Solution

1. Step 1: Write the proportion equation
   1,189.64 : 1,641.71 = 658.56 : x
2. Step 2: Convert to fraction form
   1,189.64/1,641.71 = 658.56/x
3. Step 3: Cross multiply
   1,189.64x = 1,641.71 × 658.56
4. Step 4: Simplify right side
   1,189.64x = 1,081,160.78
5. Step 5: Solve for x
   x = 1,081,160.78/1,189.64
6. Step 6: Final answer
   x = 908.81