Finding the Fourth Proportional to 1,189.38, 1,784.82 and 641.94

Step by Step Solution

1. Step 1: Write the proportion equation
   1,189.38 : 1,784.82 = 641.94 : x
2. Step 2: Convert to fraction form
   1,189.38/1,784.82 = 641.94/x
3. Step 3: Cross multiply
   1,189.38x = 1,784.82 × 641.94
4. Step 4: Simplify right side
   1,189.38x = 1,145,747.35
5. Step 5: Solve for x
   x = 1,145,747.35/1,189.38
6. Step 6: Final answer
   x = 963.31