Finding the Fourth Proportional to 3,783.72, 5,678.17 and 1,318.54

Step by Step Solution

1. Step 1: Write the proportion equation
   3,783.72 : 5,678.17 = 1,318.54 : x
2. Step 2: Convert to fraction form
   3,783.72/5,678.17 = 1,318.54/x
3. Step 3: Cross multiply
   3,783.72x = 5,678.17 × 1,318.54
4. Step 4: Simplify right side
   3,783.72x = 7,486,894.27
5. Step 5: Solve for x
   x = 7,486,894.27/3,783.72
6. Step 6: Final answer
   x = 1,978.71