Finding the Fourth Proportional to 1,189.62, 1,641.24 and 857.34

Step by Step Solution

1. Step 1: Write the proportion equation
   1,189.62 : 1,641.24 = 857.34 : x
2. Step 2: Convert to fraction form
   1,189.62/1,641.24 = 857.34/x
3. Step 3: Cross multiply
   1,189.62x = 1,641.24 × 857.34
4. Step 4: Simplify right side
   1,189.62x = 1,407,100.70
5. Step 5: Solve for x
   x = 1,407,100.70/1,189.62
6. Step 6: Final answer
   x = 1,182.82