Finding the Fourth Proportional to 1,191.66, 1,644.52 and 667.74

Step by Step Solution

1. Step 1: Write the proportion equation
   1,191.66 : 1,644.52 = 667.74 : x
2. Step 2: Convert to fraction form
   1,191.66/1,644.52 = 667.74/x
3. Step 3: Cross multiply
   1,191.66x = 1,644.52 × 667.74
4. Step 4: Simplify right side
   1,191.66x = 1,098,111.78
5. Step 5: Solve for x
   x = 1,098,111.78/1,191.66
6. Step 6: Final answer
   x = 921.50