Finding the Fourth Proportional to 1,191.27, 1,643.96 and 667.30

Step by Step Solution

1. Step 1: Write the proportion equation
   1,191.27 : 1,643.96 = 667.30 : x
2. Step 2: Convert to fraction form
   1,191.27/1,643.96 = 667.30/x
3. Step 3: Cross multiply
   1,191.27x = 1,643.96 × 667.30
4. Step 4: Simplify right side
   1,191.27x = 1,097,014.65
5. Step 5: Solve for x
   x = 1,097,014.65/1,191.27
6. Step 6: Final answer
   x = 920.88