Finding the Fourth Proportional to 12,761.40, 17,606.34 and 7,978.08

Step by Step Solution

1. Step 1: Write the proportion equation
   12,761.40 : 17,606.34 = 7,978.08 : x
2. Step 2: Convert to fraction form
   12,761.40/17,606.34 = 7,978.08/x
3. Step 3: Cross multiply
   12,761.40x = 17,606.34 × 7,978.08
4. Step 4: Simplify right side
   12,761.40x = 140,464,789.03
5. Step 5: Solve for x
   x = 140,464,789.03/12,761.40
6. Step 6: Final answer
   x = 11,007.00