Finding the Fourth Proportional to 2,528.78, 3,486.87 and 2,174.30

Step by Step Solution

1. Step 1: Write the proportion equation
   2,528.78 : 3,486.87 = 2,174.30 : x
2. Step 2: Convert to fraction form
   2,528.78/3,486.87 = 2,174.30/x
3. Step 3: Cross multiply
   2,528.78x = 3,486.87 × 2,174.30
4. Step 4: Simplify right side
   2,528.78x = 7,581,484.01
5. Step 5: Solve for x
   x = 7,581,484.01/2,528.78
6. Step 6: Final answer
   x = 2,998.09