Finding the Fourth Proportional to 2,128.51, 3,192.72 and 667.74

Step by Step Solution

1. Step 1: Write the proportion equation
   2,128.51 : 3,192.72 = 667.74 : x
2. Step 2: Convert to fraction form
   2,128.51/3,192.72 = 667.74/x
3. Step 3: Cross multiply
   2,128.51x = 3,192.72 × 667.74
4. Step 4: Simplify right side
   2,128.51x = 2,131,906.85
5. Step 5: Solve for x
   x = 2,131,906.85/2,128.51
6. Step 6: Final answer
   x = 1,001.60