Finding the Fourth Proportional to 1,189.42, 1,641.33 and 665.48

Step by Step Solution

1. Step 1: Write the proportion equation
   1,189.42 : 1,641.33 = 665.48 : x
2. Step 2: Convert to fraction form
   1,189.42/1,641.33 = 665.48/x
3. Step 3: Cross multiply
   1,189.42x = 1,641.33 × 665.48
4. Step 4: Simplify right side
   1,189.42x = 1,092,276.39
5. Step 5: Solve for x
   x = 1,092,276.39/1,189.42
6. Step 6: Final answer
   x = 918.33