Finding the Fourth Proportional to 2,611.78, 3,890.52 and 2,470.31

Step by Step Solution

1. Step 1: Write the proportion equation
   2,611.78 : 3,890.52 = 2,470.31 : x
2. Step 2: Convert to fraction form
   2,611.78/3,890.52 = 2,470.31/x
3. Step 3: Cross multiply
   2,611.78x = 3,890.52 × 2,470.31
4. Step 4: Simplify right side
   2,611.78x = 9,610,771.01
5. Step 5: Solve for x
   x = 9,610,771.01/2,611.78
6. Step 6: Final answer
   x = 3,679.78