Finding the Fourth Proportional to 2,128.55, 3,192.93 and 667.72

Step by Step Solution

1. Step 1: Write the proportion equation
   2,128.55 : 3,192.93 = 667.72 : x
2. Step 2: Convert to fraction form
   2,128.55/3,192.93 = 667.72/x
3. Step 3: Cross multiply
   2,128.55x = 3,192.93 × 667.72
4. Step 4: Simplify right side
   2,128.55x = 2,131,983.22
5. Step 5: Solve for x
   x = 2,131,983.22/2,128.55
6. Step 6: Final answer
   x = 1,001.61