Finding the Fourth Proportional to 1,653.92, 2,478.72 and 1,239.20

Step by Step Solution

1. Step 1: Write the proportion equation
   1,653.92 : 2,478.72 = 1,239.20 : x
2. Step 2: Convert to fraction form
   1,653.92/2,478.72 = 1,239.20/x
3. Step 3: Cross multiply
   1,653.92x = 2,478.72 × 1,239.20
4. Step 4: Simplify right side
   1,653.92x = 3,071,629.82
5. Step 5: Solve for x
   x = 3,071,629.82/1,653.92
6. Step 6: Final answer
   x = 1,857.18