Finding the Fourth Proportional to 1,191.09, 1,643.73 and 667.29

Step by Step Solution

1. Step 1: Write the proportion equation
   1,191.09 : 1,643.73 = 667.29 : x
2. Step 2: Convert to fraction form
   1,191.09/1,643.73 = 667.29/x
3. Step 3: Cross multiply
   1,191.09x = 1,643.73 × 667.29
4. Step 4: Simplify right side
   1,191.09x = 1,096,844.59
5. Step 5: Solve for x
   x = 1,096,844.59/1,191.09
6. Step 6: Final answer
   x = 920.87