Finding the Fourth Proportional to 2,165.40, 3,249.78 and 867.72

Step by Step Solution

1. Step 1: Write the proportion equation
   2,165.40 : 3,249.78 = 867.72 : x
2. Step 2: Convert to fraction form
   2,165.40/3,249.78 = 867.72/x
3. Step 3: Cross multiply
   2,165.40x = 3,249.78 × 867.72
4. Step 4: Simplify right side
   2,165.40x = 2,819,899.10
5. Step 5: Solve for x
   x = 2,819,899.10/2,165.40
6. Step 6: Final answer
   x = 1,302.25