Finding the Fourth Proportional to 2,820.78, 3,883.98 and 2,505.50

Step by Step Solution

1. Step 1: Write the proportion equation
   2,820.78 : 3,883.98 = 2,505.50 : x
2. Step 2: Convert to fraction form
   2,820.78/3,883.98 = 2,505.50/x
3. Step 3: Cross multiply
   2,820.78x = 3,883.98 × 2,505.50
4. Step 4: Simplify right side
   2,820.78x = 9,731,298.46
5. Step 5: Solve for x
   x = 9,731,298.46/2,820.78
6. Step 6: Final answer
   x = 3,449.86