Finding the Fourth Proportional to 1,191.99, 1,644.86 and 667.95

Step by Step Solution

1. Step 1: Write the proportion equation
   1,191.99 : 1,644.86 = 667.95 : x
2. Step 2: Convert to fraction form
   1,191.99/1,644.86 = 667.95/x
3. Step 3: Cross multiply
   1,191.99x = 1,644.86 × 667.95
4. Step 4: Simplify right side
   1,191.99x = 1,098,680.90
5. Step 5: Solve for x
   x = 1,098,680.90/1,191.99
6. Step 6: Final answer
   x = 921.72