Finding the Fourth Proportional to 1,191.38, 1,644.18 and 667.45

Step by Step Solution

1. Step 1: Write the proportion equation
   1,191.38 : 1,644.18 = 667.45 : x
2. Step 2: Convert to fraction form
   1,191.38/1,644.18 = 667.45/x
3. Step 3: Cross multiply
   1,191.38x = 1,644.18 × 667.45
4. Step 4: Simplify right side
   1,191.38x = 1,097,407.94
5. Step 5: Solve for x
   x = 1,097,407.94/1,191.38
6. Step 6: Final answer
   x = 921.12