Finding the Fourth Proportional to 2,140.48, 3,210.78 and 1,045.72

Step by Step Solution

1. Step 1: Write the proportion equation
   2,140.48 : 3,210.78 = 1,045.72 : x
2. Step 2: Convert to fraction form
   2,140.48/3,210.78 = 1,045.72/x
3. Step 3: Cross multiply
   2,140.48x = 3,210.78 × 1,045.72
4. Step 4: Simplify right side
   2,140.48x = 3,357,576.86
5. Step 5: Solve for x
   x = 3,357,576.86/2,140.48
6. Step 6: Final answer
   x = 1,568.61