Finding the Fourth Proportional to 2,139.60, 2,952.72 and 1,208.16

Step by Step Solution

1. Step 1: Write the proportion equation
   2,139.60 : 2,952.72 = 1,208.16 : x
2. Step 2: Convert to fraction form
   2,139.60/2,952.72 = 1,208.16/x
3. Step 3: Cross multiply
   2,139.60x = 2,952.72 × 1,208.16
4. Step 4: Simplify right side
   2,139.60x = 3,567,358.20
5. Step 5: Solve for x
   x = 3,567,358.20/2,139.60
6. Step 6: Final answer
   x = 1,667.30