Finding the Fourth Proportional to 3,785.63, 5,679.39 and 1,320.48

Step by Step Solution

1. Step 1: Write the proportion equation
   3,785.63 : 5,679.39 = 1,320.48 : x
2. Step 2: Convert to fraction form
   3,785.63/5,679.39 = 1,320.48/x
3. Step 3: Cross multiply
   3,785.63x = 5,679.39 × 1,320.48
4. Step 4: Simplify right side
   3,785.63x = 7,499,520.91
5. Step 5: Solve for x
   x = 7,499,520.91/3,785.63
6. Step 6: Final answer
   x = 1,981.05