Finding the Fourth Proportional to 2,128.80, 3,192.08 and 667.56

Step by Step Solution

1. Step 1: Write the proportion equation
   2,128.80 : 3,192.08 = 667.56 : x
2. Step 2: Convert to fraction form
   2,128.80/3,192.08 = 667.56/x
3. Step 3: Cross multiply
   2,128.80x = 3,192.08 × 667.56
4. Step 4: Simplify right side
   2,128.80x = 2,130,904.92
5. Step 5: Solve for x
   x = 2,130,904.92/2,128.80
6. Step 6: Final answer
   x = 1,000.99