Finding the Fourth Proportional to 10,478.81, 15,718.31 and 2,687.69

Step by Step Solution

1. Step 1: Write the proportion equation
   10,478.81 : 15,718.31 = 2,687.69 : x
2. Step 2: Convert to fraction form
   10,478.81/15,718.31 = 2,687.69/x
3. Step 3: Cross multiply
   10,478.81x = 15,718.31 × 2,687.69
4. Step 4: Simplify right side
   10,478.81x = 42,245,944.60
5. Step 5: Solve for x
   x = 42,245,944.60/10,478.81
6. Step 6: Final answer
   x = 4,031.56