Finding the Fourth Proportional to 2,128.72, 3,188.46 and 1,030.78

Step by Step Solution

1. Step 1: Write the proportion equation
   2,128.72 : 3,188.46 = 1,030.78 : x
2. Step 2: Convert to fraction form
   2,128.72/3,188.46 = 1,030.78/x
3. Step 3: Cross multiply
   2,128.72x = 3,188.46 × 1,030.78
4. Step 4: Simplify right side
   2,128.72x = 3,286,608.65
5. Step 5: Solve for x
   x = 3,286,608.65/2,128.72
6. Step 6: Final answer
   x = 1,543.94