Finding the Fourth Proportional to 7,815.70, 10,785.72 and 4,278.88

Step by Step Solution

1. Step 1: Write the proportion equation
   7,815.70 : 10,785.72 = 4,278.88 : x
2. Step 2: Convert to fraction form
   7,815.70/10,785.72 = 4,278.88/x
3. Step 3: Cross multiply
   7,815.70x = 10,785.72 × 4,278.88
4. Step 4: Simplify right side
   7,815.70x = 46,150,801.59
5. Step 5: Solve for x
   x = 46,150,801.59/7,815.70
6. Step 6: Final answer
   x = 5,904.88