Finding the Fourth Proportional to 2,783.40, 4,171.50 and 1,320.54

Step by Step Solution

1. Step 1: Write the proportion equation
   2,783.40 : 4,171.50 = 1,320.54 : x
2. Step 2: Convert to fraction form
   2,783.40/4,171.50 = 1,320.54/x
3. Step 3: Cross multiply
   2,783.40x = 4,171.50 × 1,320.54
4. Step 4: Simplify right side
   2,783.40x = 5,508,632.61
5. Step 5: Solve for x
   x = 5,508,632.61/2,783.40
6. Step 6: Final answer
   x = 1,979.10