Finding the Fourth Proportional to 2,656.58, 3,978.69 and 2,564.30

Step by Step Solution

1. Step 1: Write the proportion equation
   2,656.58 : 3,978.69 = 2,564.30 : x
2. Step 2: Convert to fraction form
   2,656.58/3,978.69 = 2,564.30/x
3. Step 3: Cross multiply
   2,656.58x = 3,978.69 × 2,564.30
4. Step 4: Simplify right side
   2,656.58x = 10,202,554.77
5. Step 5: Solve for x
   x = 10,202,554.77/2,656.58
6. Step 6: Final answer
   x = 3,840.48