Finding the Fourth Proportional to 2,164.68, 2,986.20 and 1,280.16

Step by Step Solution

1. Step 1: Write the proportion equation
   2,164.68 : 2,986.20 = 1,280.16 : x
2. Step 2: Convert to fraction form
   2,164.68/2,986.20 = 1,280.16/x
3. Step 3: Cross multiply
   2,164.68x = 2,986.20 × 1,280.16
4. Step 4: Simplify right side
   2,164.68x = 3,822,813.79
5. Step 5: Solve for x
   x = 3,822,813.79/2,164.68
6. Step 6: Final answer
   x = 1,765.99