Finding the Fourth Proportional to 2,646.47, 3,979.43 and 2,539.55

Step by Step Solution

1. Step 1: Write the proportion equation
   2,646.47 : 3,979.43 = 2,539.55 : x
2. Step 2: Convert to fraction form
   2,646.47/3,979.43 = 2,539.55/x
3. Step 3: Cross multiply
   2,646.47x = 3,979.43 × 2,539.55
4. Step 4: Simplify right side
   2,646.47x = 10,105,928.86
5. Step 5: Solve for x
   x = 10,105,928.86/2,646.47
6. Step 6: Final answer
   x = 3,818.65