Finding the Fourth Proportional to 1,189.32, 1,641.17 and 665.25

Step by Step Solution

1. Step 1: Write the proportion equation
   1,189.32 : 1,641.17 = 665.25 : x
2. Step 2: Convert to fraction form
   1,189.32/1,641.17 = 665.25/x
3. Step 3: Cross multiply
   1,189.32x = 1,641.17 × 665.25
4. Step 4: Simplify right side
   1,189.32x = 1,091,785.02
5. Step 5: Solve for x
   x = 1,091,785.02/1,189.32
6. Step 6: Final answer
   x = 917.99