Finding the Fourth Proportional to 1,668.40, 2,499.34 and 1,089.52

Step by Step Solution

1. Step 1: Write the proportion equation
   1,668.40 : 2,499.34 = 1,089.52 : x
2. Step 2: Convert to fraction form
   1,668.40/2,499.34 = 1,089.52/x
3. Step 3: Cross multiply
   1,668.40x = 2,499.34 × 1,089.52
4. Step 4: Simplify right side
   1,668.40x = 2,723,080.92
5. Step 5: Solve for x
   x = 2,723,080.92/1,668.40
6. Step 6: Final answer
   x = 1,632.15